diff --git a/CHANGELOG.md b/CHANGELOG.md
index c03b1462f66..8d33abdb766 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,6 +27,7 @@ We use *breaking* word for marking changes that are not backward compatible (rel
 - [#1714](https://github.com/thanos-io/thanos/pull/1714) Run the bucket web UI in the compact component when it is run as a long-lived process.
 - [#2304](https://github.com/thanos-io/thanos/pull/2304) Store: Added `max_item_size` config option to memcached-based index cache. This should be set to the max item size configured in memcached (`-I` flag) in order to not waste network round-trips to cache items larger than the limit configured in memcached.
 - [#2297](https://github.com/thanos-io/thanos/pull/2297) Store Gateway: Add `--experimental.enable-index-cache-postings-compression` flag to enable reencoding and compressing postings before storing them into cache. Compressed postings take about 10% of the original size.
+- [#2357](https://github.com/thanos-io/thanos/pull/2357) Compactor and Store Gateway now have serve BucketUI on `:<http-port>/loaded` and shows exactly the blocks that are currently seen by compactor and store gateway. Compactor also serves different BucketUI on `:<http-port>/global` that shows the status of object storage without any filters.
 
 ### Changed
 
diff --git a/cmd/thanos/bucket.go b/cmd/thanos/bucket.go
index 2a46098c7ca..375814fc68b 100644
--- a/cmd/thanos/bucket.go
+++ b/cmd/thanos/bucket.go
@@ -340,15 +340,10 @@ func registerBucketWeb(m map[string]setupFunc, root *kingpin.CmdClause, name str
 			httpserver.WithGracePeriod(time.Duration(*httpGracePeriod)),
 		)
 
-		flagsMap := map[string]string{
-			"web.external-prefix": *webExternalPrefix,
-			"web.prefix-header":   *webPrefixHeaderName,
-		}
-
 		router := route.New()
 
-		bucketUI := ui.NewBucketUI(logger, *label, flagsMap)
-		bucketUI.Register(router.WithPrefix(*webExternalPrefix), extpromhttp.NewInstrumentationMiddleware(reg))
+		bucketUI := ui.NewBucketUI(logger, *label, *webExternalPrefix, *webPrefixHeaderName)
+		bucketUI.Register(router, extpromhttp.NewInstrumentationMiddleware(reg))
 		srv.Handle("/", router)
 
 		if *interval < 5*time.Minute {
@@ -373,17 +368,29 @@ func registerBucketWeb(m map[string]setupFunc, root *kingpin.CmdClause, name str
 			return errors.Wrap(err, "bucket client")
 		}
 
-		// TODO(bwplotka): Allow Bucket UI to visualisate the state of block as well.
+		// TODO(bwplotka): Allow Bucket UI to visualize the state of block as well.
 		fetcher, err := block.NewMetaFetcher(logger, fetcherConcurrency, bkt, "", extprom.WrapRegistererWithPrefix(extpromPrefix, reg), nil, nil)
 		if err != nil {
 			return err
 		}
+		fetcher.UpdateOnChange(bucketUI.Set)
 
 		ctx, cancel := context.WithCancel(context.Background())
 		g.Add(func() error {
 			statusProber.Ready()
 			defer runutil.CloseWithLogOnErr(logger, bkt, "bucket client")
-			return bucketUI.RunRefreshLoop(ctx, fetcher, *interval, *timeout)
+			return runutil.Repeat(*interval, ctx.Done(), func() error {
+				return runutil.RetryWithLog(logger, time.Minute, ctx.Done(), func() error {
+					iterCtx, iterCancel := context.WithTimeout(ctx, *timeout)
+					defer iterCancel()
+
+					_, _, err := fetcher.Fetch(iterCtx)
+					if err != nil {
+						return err
+					}
+					return nil
+				})
+			})
 		}, func(error) {
 			cancel()
 		})
diff --git a/cmd/thanos/compact.go b/cmd/thanos/compact.go
index 409cbe8d2f8..0b1c22769f6 100644
--- a/cmd/thanos/compact.go
+++ b/cmd/thanos/compact.go
@@ -146,11 +146,6 @@ func registerCompact(m map[string]setupFunc, app *kingpin.Application) {
 
 	webExternalPrefix := cmd.Flag("web.external-prefix", "Static prefix for all HTML links and redirect URLs in the bucket web UI interface. Actual endpoints are still served on / or the web.route-prefix. This allows thanos bucket web UI to be served behind a reverse proxy that strips a URL sub-path.").Default("").String()
 	webPrefixHeaderName := cmd.Flag("web.prefix-header", "Name of HTTP request header used for dynamic prefixing of UI links and redirects. This option is ignored if web.external-prefix argument is set. Security risk: enable this option only if a reverse proxy in front of thanos is resetting the header. The --web.prefix-header=X-Forwarded-Prefix option can be useful, for example, if Thanos UI is served via Traefik reverse proxy with PathPrefixStrip option enabled, which sends the stripped prefix value in X-Forwarded-Prefix header. This allows thanos UI to be served on a sub-path.").Default("").String()
-	flagsMap := map[string]string{
-		"web.external-prefix": *webExternalPrefix,
-		"web.prefix-header":   *webPrefixHeaderName,
-	}
-
 	label := cmd.Flag("bucket-web-label", "Prometheus label to use as timeline title in the bucket web UI").String()
 
 	m[component.Compact.String()] = func(g *run.Group, logger log.Logger, reg *prometheus.Registry, tracer opentracing.Tracer, _ <-chan struct{}, _ bool) error {
@@ -179,7 +174,8 @@ func registerCompact(m map[string]setupFunc, app *kingpin.Application) {
 			selectorRelabelConf,
 			*waitInterval,
 			*label,
-			flagsMap,
+			*webExternalPrefix,
+			*webPrefixHeaderName,
 		)
 	}
 }
@@ -194,21 +190,17 @@ func runCompact(
 	objStoreConfig *extflag.PathOrContent,
 	consistencyDelay time.Duration,
 	deleteDelay time.Duration,
-	haltOnError bool,
-	acceptMalformedIndex bool,
-	wait bool,
-	generateMissingIndexCacheFiles bool,
+	haltOnError, acceptMalformedIndex, wait, generateMissingIndexCacheFiles bool,
 	retentionByResolution map[compact.ResolutionLevel]time.Duration,
 	component component.Component,
 	disableDownsampling bool,
-	maxCompactionLevel int,
-	blockSyncConcurrency int,
+	maxCompactionLevel, blockSyncConcurrency int,
 	concurrency int,
 	dedupReplicaLabels []string,
 	selectorRelabelConf *extflag.PathOrContent,
 	waitInterval time.Duration,
 	label string,
-	flagsMap map[string]string,
+	externalPrefix, prefixHeader string,
 ) error {
 	halted := promauto.With(reg).NewGauge(prometheus.GaugeOpts{
 		Name: "thanos_compactor_halted",
@@ -306,13 +298,12 @@ func runCompact(
 	if err != nil {
 		return errors.Wrap(err, "create meta fetcher")
 	}
-	metaFetcherFilters := []block.MetadataFilter{
+	compactFetcher := baseMetaFetcher.NewMetaFetcher(extprom.WrapRegistererWithPrefix("thanos_", reg), []block.MetadataFilter{
 		block.NewLabelShardedMetaFilter(relabelConfig),
 		block.NewConsistencyDelayMetaFilter(logger, consistencyDelay, extprom.WrapRegistererWithPrefix("thanos_", reg)),
 		ignoreDeletionMarkFilter,
 		duplicateBlocksFilter,
-	}
-	compactFetcher := baseMetaFetcher.WithFilters(extprom.WrapRegistererWithPrefix("thanos_", reg), metaFetcherFilters, []block.MetadataModifier{block.NewReplicaLabelRemover(logger, dedupReplicaLabels)})
+	}, []block.MetadataModifier{block.NewReplicaLabelRemover(logger, dedupReplicaLabels)})
 	enableVerticalCompaction := false
 	if len(dedupReplicaLabels) > 0 {
 		enableVerticalCompaction = true
@@ -457,14 +448,41 @@ func runCompact(
 	})
 
 	if wait {
-		router := route.New()
-		bucketUI := ui.NewBucketUI(logger, label, flagsMap)
-		bucketUI.Register(router, extpromhttp.NewInstrumentationMiddleware(reg))
-		srv.Handle("/", router)
+		r := route.New()
+
+		ins := extpromhttp.NewInstrumentationMiddleware(reg)
+		compactorView := ui.NewBucketUI(logger, label, path.Join(externalPrefix, "/loaded"), prefixHeader)
+		compactorView.Register(r, ins)
+		compactFetcher.UpdateOnChange(compactorView.Set)
+
+		global := ui.NewBucketUI(logger, label, path.Join(externalPrefix, "/global"), prefixHeader)
+		global.Register(r, ins)
+
+		// Separate fetcher for global view.
+		// TODO(bwplotka): Allow Bucket UI to visualize the state of the block as well.
+		f := baseMetaFetcher.NewMetaFetcher(extprom.WrapRegistererWithPrefix("thanos_bucket_ui", reg), nil, nil)
+		f.UpdateOnChange(global.Set)
+
+		srv.Handle("/", r)
 
 		g.Add(func() error {
-			// TODO(bwplotka): Allow Bucket UI to visualisate the state of the block as well.
-			return bucketUI.RunRefreshLoop(ctx, baseMetaFetcher.WithFilters(extprom.WrapRegistererWithPrefix("thanos_bucket_ui", reg), metaFetcherFilters, nil), waitInterval, time.Minute)
+			iterCtx, iterCancel := context.WithTimeout(ctx, waitInterval)
+			_, _, _ = f.Fetch(iterCtx)
+			iterCancel()
+
+			// For /global state make sure to fetch periodically.
+			return runutil.Repeat(time.Minute, ctx.Done(), func() error {
+				return runutil.RetryWithLog(logger, time.Minute, ctx.Done(), func() error {
+					iterCtx, iterCancel := context.WithTimeout(ctx, waitInterval)
+					defer iterCancel()
+
+					_, _, err := f.Fetch(iterCtx)
+					if err != nil {
+						return err
+					}
+					return nil
+				})
+			})
 		}, func(error) {
 			cancel()
 		})
diff --git a/cmd/thanos/query.go b/cmd/thanos/query.go
index 4a352f35aac..a21565c59a4 100644
--- a/cmd/thanos/query.go
+++ b/cmd/thanos/query.go
@@ -351,14 +351,9 @@ func runQuery(
 			router = router.WithPrefix(webRoutePrefix)
 		}
 
-		flagsMap := map[string]string{
-			// TODO(bplotka in PR #513 review): pass all flags, not only the flags needed by prefix rewriting.
-			"web.external-prefix": webExternalPrefix,
-			"web.prefix-header":   webPrefixHeaderName,
-		}
-
 		ins := extpromhttp.NewInstrumentationMiddleware(reg)
-		ui.NewQueryUI(logger, reg, stores, flagsMap).Register(router, ins)
+		// TODO(bplotka in PR #513 review): pass all flags, not only the flags needed by prefix rewriting.
+		ui.NewQueryUI(logger, reg, stores, webExternalPrefix, webPrefixHeaderName).Register(router, ins)
 
 		api := v1.NewAPI(logger, reg, engine, queryableCreator, enableAutodownsampling, enablePartialResponse, replicaLabels, instantDefaultMaxSourceResolution)
 
diff --git a/cmd/thanos/rule.go b/cmd/thanos/rule.go
index 290ec41c00b..553272282b6 100644
--- a/cmd/thanos/rule.go
+++ b/cmd/thanos/rule.go
@@ -572,15 +572,10 @@ func runRule(
 			}
 		})
 
-		flagsMap := map[string]string{
-			// TODO(bplotka in PR #513 review): pass all flags, not only the flags needed by prefix rewriting.
-			"web.external-prefix": webExternalPrefix,
-			"web.prefix-header":   webPrefixHeaderName,
-		}
-
 		ins := extpromhttp.NewInstrumentationMiddleware(reg)
 
-		ui.NewRuleUI(logger, reg, ruleMgr, alertQueryURL.String(), flagsMap).Register(router, ins)
+		// TODO(bplotka in PR #513 review): pass all flags, not only the flags needed by prefix rewriting.
+		ui.NewRuleUI(logger, reg, ruleMgr, alertQueryURL.String(), webExternalPrefix, webPrefixHeaderName).Register(router, ins)
 
 		api := v1.NewAPI(logger, reg, ruleMgr)
 		api.Register(router.WithPrefix(path.Join(webRoutePrefix, "/api/v1")), tracer, logger, ins)
diff --git a/cmd/thanos/store.go b/cmd/thanos/store.go
index 446077530c4..54421d6e490 100644
--- a/cmd/thanos/store.go
+++ b/cmd/thanos/store.go
@@ -5,6 +5,7 @@ package main
 
 import (
 	"context"
+	"path"
 	"time"
 
 	"github.com/go-kit/kit/log"
@@ -13,11 +14,13 @@ import (
 	"github.com/opentracing/opentracing-go"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/common/route"
 	"github.com/prometheus/prometheus/pkg/relabel"
 	"github.com/thanos-io/thanos/pkg/block"
 	"github.com/thanos-io/thanos/pkg/component"
 	"github.com/thanos-io/thanos/pkg/extflag"
 	"github.com/thanos-io/thanos/pkg/extprom"
+	extpromhttp "github.com/thanos-io/thanos/pkg/extprom/http"
 	"github.com/thanos-io/thanos/pkg/model"
 	"github.com/thanos-io/thanos/pkg/objstore/client"
 	"github.com/thanos-io/thanos/pkg/prober"
@@ -27,6 +30,7 @@ import (
 	"github.com/thanos-io/thanos/pkg/store"
 	storecache "github.com/thanos-io/thanos/pkg/store/cache"
 	"github.com/thanos-io/thanos/pkg/tls"
+	"github.com/thanos-io/thanos/pkg/ui"
 	"gopkg.in/alecthomas/kingpin.v2"
 	yaml "gopkg.in/yaml.v2"
 )
@@ -95,6 +99,9 @@ func registerStore(m map[string]setupFunc, app *kingpin.Application) {
 		"Default is 24h, half of the default value for --delete-delay on compactor.").
 		Default("24h"))
 
+	webExternalPrefix := cmd.Flag("web.external-prefix", "Static prefix for all HTML links and redirect URLs in the bucket web UI interface. Actual endpoints are still served on / or the web.route-prefix. This allows thanos bucket web UI to be served behind a reverse proxy that strips a URL sub-path.").Default("").String()
+	webPrefixHeaderName := cmd.Flag("web.prefix-header", "Name of HTTP request header used for dynamic prefixing of UI links and redirects. This option is ignored if web.external-prefix argument is set. Security risk: enable this option only if a reverse proxy in front of thanos is resetting the header. The --web.prefix-header=X-Forwarded-Prefix option can be useful, for example, if Thanos UI is served via Traefik reverse proxy with PathPrefixStrip option enabled, which sends the stripped prefix value in X-Forwarded-Prefix header. This allows thanos UI to be served on a sub-path.").Default("").String()
+
 	m[component.Store.String()] = func(g *run.Group, logger log.Logger, reg *prometheus.Registry, tracer opentracing.Tracer, _ <-chan struct{}, debugLogging bool) error {
 		if minTime.PrometheusTimestamp() > maxTime.PrometheusTimestamp() {
 			return errors.Errorf("invalid argument: --min-time '%s' can't be greater than --max-time '%s'",
@@ -133,6 +140,8 @@ func registerStore(m map[string]setupFunc, app *kingpin.Application) {
 			*enablePostingsCompression,
 			time.Duration(*consistencyDelay),
 			time.Duration(*ignoreDeletionMarksDelay),
+			*webExternalPrefix,
+			*webPrefixHeaderName,
 		)
 	}
 }
@@ -148,14 +157,9 @@ func runStore(
 	dataDir string,
 	grpcBindAddr string,
 	grpcGracePeriod time.Duration,
-	grpcCert string,
-	grpcKey string,
-	grpcClientCA string,
-	httpBindAddr string,
+	grpcCert, grpcKey, grpcClientCA, httpBindAddr string,
 	httpGracePeriod time.Duration,
-	indexCacheSizeBytes uint64,
-	chunkPoolSizeBytes uint64,
-	maxSampleCount uint64,
+	indexCacheSizeBytes, chunkPoolSizeBytes, maxSampleCount uint64,
 	maxConcurrency int,
 	component component.Component,
 	verbose bool,
@@ -163,11 +167,10 @@ func runStore(
 	blockSyncConcurrency int,
 	filterConf *store.FilterConfig,
 	selectorRelabelConf *extflag.PathOrContent,
-	advertiseCompatibilityLabel bool,
-	disableIndexHeader bool,
-	enablePostingsCompression bool,
+	advertiseCompatibilityLabel, disableIndexHeader, enablePostingsCompression bool,
 	consistencyDelay time.Duration,
 	ignoreDeletionMarksDelay time.Duration,
+	externalPrefix, prefixHeader string,
 ) error {
 	grpcProbe := prober.NewGRPC()
 	httpProbe := prober.NewHTTP()
@@ -328,6 +331,14 @@ func runStore(
 			s.Shutdown(err)
 		})
 	}
+	// Add bucket UI for loaded blocks.
+	{
+		r := route.New()
+		compactorView := ui.NewBucketUI(logger, "", path.Join(externalPrefix, "/loaded"), prefixHeader)
+		compactorView.Register(r, extpromhttp.NewInstrumentationMiddleware(reg))
+		metaFetcher.UpdateOnChange(compactorView.Set)
+		srv.Handle("/", r)
+	}
 
 	level.Info(logger).Log("msg", "starting store node")
 	return nil
diff --git a/pkg/block/fetcher.go b/pkg/block/fetcher.go
index 10ca88e17bc..e83bc5633dd 100644
--- a/pkg/block/fetcher.go
+++ b/pkg/block/fetcher.go
@@ -116,7 +116,7 @@ func newFetcherMetrics(reg prometheus.Registerer) *fetcherMetrics {
 		prometheus.GaugeOpts{
 			Subsystem: fetcherSubSys,
 			Name:      "modified",
-			Help:      "Number of blocks that their metadata modified",
+			Help:      "Number of blocks whose metadata changed",
 		},
 		[]string{"modified"},
 		[]string{replicaRemovedMeta},
@@ -126,6 +126,7 @@ func newFetcherMetrics(reg prometheus.Registerer) *fetcherMetrics {
 
 type MetadataFetcher interface {
 	Fetch(ctx context.Context) (metas map[ulid.ULID]*metadata.Meta, partial map[ulid.ULID]error, err error)
+	UpdateOnChange(func([]metadata.Meta, error))
 }
 
 type MetadataFilter interface {
@@ -184,11 +185,11 @@ func NewMetaFetcher(logger log.Logger, concurrency int, bkt objstore.BucketReade
 	if err != nil {
 		return nil, err
 	}
-	return b.WithFilters(reg, filters, modifiers), nil
+	return b.NewMetaFetcher(reg, filters, modifiers), nil
 }
 
-// WithFilters transforms BaseFetcher into actually usable MetadataFetcher.
-func (f *BaseFetcher) WithFilters(reg prometheus.Registerer, filters []MetadataFilter, modifiers []MetadataModifier) *MetaFetcher {
+// NewMetaFetcher transforms BaseFetcher into actually usable *MetaFetcher.
+func (f *BaseFetcher) NewMetaFetcher(reg prometheus.Registerer, filters []MetadataFilter, modifiers []MetadataModifier) *MetaFetcher {
 	return &MetaFetcher{metrics: newFetcherMetrics(reg), wrapped: f, filters: filters, modifiers: modifiers}
 }
 
@@ -457,6 +458,8 @@ type MetaFetcher struct {
 
 	filters   []MetadataFilter
 	modifiers []MetadataModifier
+
+	listener func([]metadata.Meta, error)
 }
 
 // Fetch returns all block metas as well as partial blocks (blocks without or with corrupted meta file) from the bucket.
@@ -464,7 +467,20 @@ type MetaFetcher struct {
 //
 // Returned error indicates a failure in fetching metadata. Returned meta can be assumed as correct, with some blocks missing.
 func (f *MetaFetcher) Fetch(ctx context.Context) (metas map[ulid.ULID]*metadata.Meta, partial map[ulid.ULID]error, err error) {
-	return f.wrapped.fetch(ctx, f.metrics, f.filters, f.modifiers)
+	metas, partial, err = f.wrapped.fetch(ctx, f.metrics, f.filters, f.modifiers)
+	if f.listener != nil {
+		blocks := make([]metadata.Meta, 0, len(metas))
+		for _, meta := range metas {
+			blocks = append(blocks, *meta)
+		}
+		f.listener(blocks, err)
+	}
+	return metas, partial, err
+}
+
+// UpdateOnChange allows to add listener that will be update on every change.
+func (f *MetaFetcher) UpdateOnChange(listener func([]metadata.Meta, error)) {
+	f.listener = listener
 }
 
 var _ MetadataFilter = &TimePartitionMetaFilter{}
@@ -558,7 +574,7 @@ func (f *DeduplicateFilter) Filter(_ context.Context, metas map[ulid.ULID]*metad
 				BlockMeta: tsdb.BlockMeta{
 					ULID: ulid.MustNew(uint64(0), nil),
 				},
-			}), metasByResolution[res], metas, res, synced)
+			}), metasByResolution[res], metas, synced)
 		}(res)
 	}
 
@@ -567,7 +583,7 @@ func (f *DeduplicateFilter) Filter(_ context.Context, metas map[ulid.ULID]*metad
 	return nil
 }
 
-func (f *DeduplicateFilter) filterForResolution(root *Node, metaSlice []*metadata.Meta, metas map[ulid.ULID]*metadata.Meta, res int64, synced *extprom.TxGaugeVec) {
+func (f *DeduplicateFilter) filterForResolution(root *Node, metaSlice []*metadata.Meta, metas map[ulid.ULID]*metadata.Meta, synced *extprom.TxGaugeVec) {
 	sort.Slice(metaSlice, func(i, j int) bool {
 		ilen := len(metaSlice[i].Compaction.Sources)
 		jlen := len(metaSlice[j].Compaction.Sources)
diff --git a/pkg/block/fetcher_test.go b/pkg/block/fetcher_test.go
index cd7b3ffade4..953ed93f4fe 100644
--- a/pkg/block/fetcher_test.go
+++ b/pkg/block/fetcher_test.go
@@ -78,7 +78,7 @@ func TestMetaFetcher_Fetch(t *testing.T) {
 		baseFetcher, err := NewBaseFetcher(log.NewNopLogger(), 20, bkt, dir, r)
 		testutil.Ok(t, err)
 
-		fetcher := baseFetcher.WithFilters(r, []MetadataFilter{
+		fetcher := baseFetcher.NewMetaFetcher(r, []MetadataFilter{
 			&ulidFilter{ulidToDelete: &ulidToDelete},
 		}, nil)
 
diff --git a/pkg/ui/bucket.go b/pkg/ui/bucket.go
index fdd1aeba432..2901b3cb0c7 100644
--- a/pkg/ui/bucket.go
+++ b/pkg/ui/bucket.go
@@ -4,25 +4,22 @@
 package ui
 
 import (
-	"context"
 	"encoding/json"
 	"html/template"
 	"net/http"
 	"time"
 
 	"github.com/go-kit/kit/log"
-	"github.com/go-kit/kit/log/level"
 	"github.com/prometheus/common/route"
-	"github.com/thanos-io/thanos/pkg/block"
 	"github.com/thanos-io/thanos/pkg/block/metadata"
 	extpromhttp "github.com/thanos-io/thanos/pkg/extprom/http"
-	"github.com/thanos-io/thanos/pkg/runutil"
 )
 
 // Bucket is a web UI representing state of buckets as a timeline.
 type Bucket struct {
 	*BaseUI
-	flagsMap map[string]string
+
+	externalPrefix, prefixHeader string
 	// Unique Prometheus label that identifies each shard, used as the title. If
 	// not present, all labels are displayed externally as a legend.
 	Label       string
@@ -31,65 +28,45 @@ type Bucket struct {
 	Err         error
 }
 
-func NewBucketUI(logger log.Logger, label string, flagsMap map[string]string) *Bucket {
+func NewBucketUI(logger log.Logger, label, externalPrefix, prefixHeader string) *Bucket {
 	return &Bucket{
-		BaseUI:   NewBaseUI(log.With(logger, "component", "bucketUI"), "bucket_menu.html", queryTmplFuncs()),
-		Blocks:   "[]",
-		Label:    label,
-		flagsMap: flagsMap,
+		BaseUI:         NewBaseUI(log.With(logger, "component", "bucketUI"), "bucket_menu.html", queryTmplFuncs()),
+		Blocks:         "[]",
+		Label:          label,
+		externalPrefix: externalPrefix,
+		prefixHeader:   prefixHeader,
 	}
 }
 
 // Register registers http routes for bucket UI.
 func (b *Bucket) Register(r *route.Router, ins extpromhttp.InstrumentationMiddleware) {
 	instrf := func(name string, next func(w http.ResponseWriter, r *http.Request)) http.HandlerFunc {
-		return ins.NewHandler(name, http.HandlerFunc(next))
+		return ins.NewHandler(b.externalPrefix+name, http.HandlerFunc(next))
 	}
-
-	r.Get("/", instrf("root", b.root))
-	r.Get("/static/*filepath", instrf("static", b.serveStaticAsset))
+	r.WithPrefix(b.externalPrefix).Get("/", instrf("root", b.root))
+	r.WithPrefix(b.externalPrefix).Get("/static/*filepath", instrf("static", b.serveStaticAsset))
 }
 
 // Handle / of bucket UIs.
 func (b *Bucket) root(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(b.logger, b.flagsMap, r)
-	b.executeTemplate(w, "bucket.html", prefix, b)
+	b.executeTemplate(w, "bucket.html", GetWebPrefix(b.logger, b.externalPrefix, b.prefixHeader, r), b)
 }
 
-func (b *Bucket) Set(data string, err error) {
+func (b *Bucket) Set(blocks []metadata.Meta, err error) {
+	if err != nil {
+		// Last view is maintained.
+		b.RefreshedAt = time.Now()
+		b.Err = err
+		return
+	}
+
+	data := "[]"
+	dataB, err := json.Marshal(blocks)
+	if err == nil {
+		data = string(dataB)
+	}
+
 	b.RefreshedAt = time.Now()
 	b.Blocks = template.JS(data)
 	b.Err = err
 }
-
-// RunRefreshLoop refreshes periodically metadata from remote storage periodically and update the UI.
-func (b *Bucket) RunRefreshLoop(ctx context.Context, fetcher block.MetadataFetcher, interval time.Duration, loopTimeout time.Duration) error {
-	return runutil.Repeat(interval, ctx.Done(), func() error {
-		return runutil.RetryWithLog(b.logger, time.Minute, ctx.Done(), func() error {
-			iterCtx, iterCancel := context.WithTimeout(ctx, loopTimeout)
-			defer iterCancel()
-
-			level.Debug(b.logger).Log("msg", "synchronizing block metadata")
-			metas, _, err := fetcher.Fetch(iterCtx)
-			if err != nil {
-				level.Error(b.logger).Log("msg", "failed to sync metas", "err", err)
-				b.Set("[]", err)
-				return err
-			}
-			blocks := make([]metadata.Meta, 0, len(metas))
-			for _, meta := range metas {
-				blocks = append(blocks, *meta)
-			}
-			level.Debug(b.logger).Log("msg", "downloaded blocks meta.json", "num", len(blocks))
-
-			data, err := json.Marshal(blocks)
-			if err != nil {
-				b.Set("[]", err)
-				return err
-			}
-			// TODO(bwplotka): Allow setting info about partial blocks as well.
-			b.Set(string(data), nil)
-			return nil
-		})
-	})
-}
diff --git a/pkg/ui/query.go b/pkg/ui/query.go
index 37660c05bf2..9f1f8accba2 100644
--- a/pkg/ui/query.go
+++ b/pkg/ui/query.go
@@ -26,7 +26,7 @@ type Query struct {
 	*BaseUI
 	storeSet *query.StoreSet
 
-	flagsMap map[string]string
+	externalPrefix, prefixHeader string
 
 	cwd   string
 	birth time.Time
@@ -43,19 +43,20 @@ type thanosVersion struct {
 	GoVersion string `json:"goVersion"`
 }
 
-func NewQueryUI(logger log.Logger, reg prometheus.Registerer, storeSet *query.StoreSet, flagsMap map[string]string) *Query {
+func NewQueryUI(logger log.Logger, reg prometheus.Registerer, storeSet *query.StoreSet, externalPrefix, prefixHeader string) *Query {
 	cwd, err := os.Getwd()
 	if err != nil {
 		cwd = "<error retrieving current working directory>"
 	}
 	return &Query{
-		BaseUI:   NewBaseUI(logger, "query_menu.html", queryTmplFuncs()),
-		storeSet: storeSet,
-		flagsMap: flagsMap,
-		cwd:      cwd,
-		birth:    time.Now(),
-		reg:      reg,
-		now:      model.Now,
+		BaseUI:         NewBaseUI(logger, "query_menu.html", queryTmplFuncs()),
+		storeSet:       storeSet,
+		externalPrefix: externalPrefix,
+		prefixHeader:   prefixHeader,
+		cwd:            cwd,
+		birth:          time.Now(),
+		reg:            reg,
+		now:            model.Now,
 	}
 }
 
@@ -90,19 +91,19 @@ func (q *Query) Register(r *route.Router, ins extpromhttp.InstrumentationMiddlew
 
 // Root redirects "/" requests to "/graph", taking into account the path prefix value.
 func (q *Query) root(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(q.logger, q.flagsMap, r)
+	prefix := GetWebPrefix(q.logger, q.externalPrefix, q.prefixHeader, r)
 
 	http.Redirect(w, r, path.Join(prefix, "/graph"), http.StatusFound)
 }
 
 func (q *Query) graph(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(q.logger, q.flagsMap, r)
+	prefix := GetWebPrefix(q.logger, q.externalPrefix, q.prefixHeader, r)
 
 	q.executeTemplate(w, "graph.html", prefix, nil)
 }
 
 func (q *Query) status(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(q.logger, q.flagsMap, r)
+	prefix := GetWebPrefix(q.logger, q.externalPrefix, q.prefixHeader, r)
 
 	q.executeTemplate(w, "status.html", prefix, struct {
 		Birth   time.Time
@@ -123,7 +124,7 @@ func (q *Query) status(w http.ResponseWriter, r *http.Request) {
 }
 
 func (q *Query) stores(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(q.logger, q.flagsMap, r)
+	prefix := GetWebPrefix(q.logger, q.externalPrefix, q.prefixHeader, r)
 	statuses := make(map[component.StoreAPI][]query.StoreStatus)
 	for _, status := range q.storeSet.GetStoreStatus() {
 		statuses[status.StoreType] = append(statuses[status.StoreType], status)
diff --git a/pkg/ui/rule.go b/pkg/ui/rule.go
index 22ab0f3ba6e..18828291293 100644
--- a/pkg/ui/rule.go
+++ b/pkg/ui/rule.go
@@ -23,20 +23,21 @@ import (
 type Rule struct {
 	*BaseUI
 
-	flagsMap map[string]string
+	externalPrefix, prefixHeader string
 
 	ruleManager *thanosrule.Manager
 	queryURL    string
 	reg         prometheus.Registerer
 }
 
-func NewRuleUI(logger log.Logger, reg prometheus.Registerer, ruleManager *thanosrule.Manager, queryURL string, flagsMap map[string]string) *Rule {
+func NewRuleUI(logger log.Logger, reg prometheus.Registerer, ruleManager *thanosrule.Manager, queryURL string, externalPrefix, prefixHeader string) *Rule {
 	return &Rule{
-		BaseUI:      NewBaseUI(logger, "rule_menu.html", ruleTmplFuncs(queryURL)),
-		flagsMap:    flagsMap,
-		ruleManager: ruleManager,
-		queryURL:    queryURL,
-		reg:         reg,
+		BaseUI:         NewBaseUI(logger, "rule_menu.html", ruleTmplFuncs(queryURL)),
+		externalPrefix: externalPrefix,
+		prefixHeader:   prefixHeader,
+		ruleManager:    ruleManager,
+		queryURL:       queryURL,
+		reg:            reg,
 	}
 }
 
@@ -133,14 +134,14 @@ func (ru *Rule) alerts(w http.ResponseWriter, r *http.Request) {
 		Counts: alertCounts(groups),
 	}
 
-	prefix := GetWebPrefix(ru.logger, ru.flagsMap, r)
+	prefix := GetWebPrefix(ru.logger, ru.externalPrefix, ru.prefixHeader, r)
 
 	// TODO(bwplotka): Update HTML to include partial response.
 	ru.executeTemplate(w, "alerts.html", prefix, alertStatus)
 }
 
 func (ru *Rule) rules(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(ru.logger, ru.flagsMap, r)
+	prefix := GetWebPrefix(ru.logger, ru.externalPrefix, ru.prefixHeader, r)
 
 	// TODO(bwplotka): Update HTML to include partial response.
 	ru.executeTemplate(w, "rules.html", prefix, ru.ruleManager)
@@ -148,7 +149,7 @@ func (ru *Rule) rules(w http.ResponseWriter, r *http.Request) {
 
 // Root redirects / requests to /graph, taking into account the path prefix value.
 func (ru *Rule) root(w http.ResponseWriter, r *http.Request) {
-	prefix := GetWebPrefix(ru.logger, ru.flagsMap, r)
+	prefix := GetWebPrefix(ru.logger, ru.externalPrefix, ru.prefixHeader, r)
 
 	http.Redirect(w, r, path.Join(prefix, "/alerts"), http.StatusFound)
 }
diff --git a/pkg/ui/ui.go b/pkg/ui/ui.go
index 269b22cd9c1..aded58c7413 100644
--- a/pkg/ui/ui.go
+++ b/pkg/ui/ui.go
@@ -92,13 +92,13 @@ func (bu *BaseUI) executeTemplate(w http.ResponseWriter, name string, prefix str
 
 // GetWebPrefix sanitizes an external URL path prefix value.
 // A value provided by web.external-prefix flag is preferred over the one supplied through an HTTP header.
-func GetWebPrefix(logger log.Logger, flagsMap map[string]string, r *http.Request) string {
+func GetWebPrefix(logger log.Logger, externalPrefix, prefixHeader string, r *http.Request) string {
 	// Ignore web.prefix-header value if web.external-prefix is defined.
-	if len(flagsMap["web.external-prefix"]) > 0 {
-		return flagsMap["web.external-prefix"]
+	if len(externalPrefix) > 0 {
+		return externalPrefix
 	}
 
-	prefix := r.Header.Get(flagsMap["web.prefix-header"])
+	prefix := r.Header.Get(prefixHeader)
 
 	// Even if rfc2616 suggests that Location header "value consists of a single absolute URI", browsers
 	// support relative location too. So for extra security, scheme and host parts are stripped from a dynamic prefix.
diff --git a/test/e2e/compact_test.go b/test/e2e/compact_test.go
index 12559615220..87c1c5eae49 100644
--- a/test/e2e/compact_test.go
+++ b/test/e2e/compact_test.go
@@ -6,6 +6,7 @@ package e2e_test
 import (
 	"context"
 	"fmt"
+	"net/http"
 	"os"
 	"path"
 	"path/filepath"
@@ -372,6 +373,11 @@ func TestCompactWithStoreGateway(t *testing.T) {
 
 		testutil.Ok(t, c.WaitSumMetrics(e2e.Equals(0), "thanos_compact_downsample_total"))
 		testutil.Ok(t, c.WaitSumMetrics(e2e.Equals(0), "thanos_compact_downsample_failures_total"))
+
+		// Ensure bucket UI.
+		ensureGETStatusCode(t, http.StatusOK, path.Join(c.HTTPEndpoint(), "global"))
+		ensureGETStatusCode(t, http.StatusOK, path.Join(c.HTTPEndpoint(), "loaded"))
+
 		testutil.Ok(t, s.Stop(c))
 	})
 	t.Run("native vertical deduplication should kick in", func(t *testing.T) {
@@ -453,3 +459,9 @@ func TestCompactWithStoreGateway(t *testing.T) {
 		testutil.Ok(t, str.WaitSumMetrics(e2e.Equals(0), "thanos_blocks_meta_modified"))
 	})
 }
+
+func ensureGETStatusCode(t testing.TB, code int, url string) {
+	r, err := http.Get(url)
+	testutil.Ok(t, err)
+	testutil.Equals(t, code, r.StatusCode)
+}
diff --git a/test/e2e/store_gateway_test.go b/test/e2e/store_gateway_test.go
index 27d736eaa99..1a0756cdc75 100644
--- a/test/e2e/store_gateway_test.go
+++ b/test/e2e/store_gateway_test.go
@@ -5,6 +5,7 @@ package e2e_test
 
 import (
 	"context"
+	"net/http"
 	"os"
 	"path"
 	"path/filepath"
@@ -56,6 +57,8 @@ func TestStoreGateway(t *testing.T) {
 	})
 	testutil.Ok(t, err)
 	testutil.Ok(t, s.StartAndWaitReady(s1))
+	// Ensure bucket UI.
+	ensureGETStatusCode(t, http.StatusOK, path.Join(s1.HTTPEndpoint(), "loaded"))
 
 	q, err := e2ethanos.NewQuerier(
 		s.SharedDir(), "1",