diff --git a/platform/chromium/webext.js b/platform/chromium/webext.js
index a0c24c228..851b653e2 100644
--- a/platform/chromium/webext.js
+++ b/platform/chromium/webext.js
@@ -156,15 +156,6 @@ if ( chrome.storage.sync instanceof Object ) {
     };
 }
 
-// https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/storage/session
-webext.storage.session = {
-    clear: ( ) => Promise.resolve(),
-    get: ( ) => Promise.resolve(),
-    getBytesInUse: ( ) => Promise.resolve(),
-    remove: ( ) => Promise.resolve(),
-    set: ( ) => Promise.resolve(),
-};
-
 // https://bugs.chromium.org/p/chromium/issues/detail?id=608854
 if ( chrome.tabs.removeCSS instanceof Function ) {
     webext.tabs.removeCSS = promisifyNoFail(chrome.tabs, 'removeCSS');
diff --git a/platform/common/vapi-background.js b/platform/common/vapi-background.js
index 08cfd5872..83d04a9af 100644
--- a/platform/common/vapi-background.js
+++ b/platform/common/vapi-background.js
@@ -109,7 +109,7 @@ vAPI.generateSecret = (size = 1) => {
  * 
  * */
 
-vAPI.sessionStorage = {
+vAPI.sessionStorage = webext.storage.session || {
     get() {
         return Promise.resolve({});
     },
@@ -122,7 +122,6 @@ vAPI.sessionStorage = {
     clear() {
         return Promise.resolve();
     },
-    implemented: false,
 };
 
 /*******************************************************************************
@@ -137,46 +136,21 @@ vAPI.sessionStorage = {
 
 vAPI.storage = {
     get(key, ...args) {
-        if ( vAPI.sessionStorage.implemented !== true ) {
-            return webext.storage.local.get(key, ...args).catch(reason => {
-                console.log(reason);
-            });
-        }
-        return vAPI.sessionStorage.get(key, ...args).then(bin => {
-            const size = Object.keys(bin).length;
-            if ( size === 1 && typeof key === 'string' && bin[key] === null ) {
-                return {};
-            }
-            if ( size !== 0 ) { return bin; }
-            return webext.storage.local.get(key, ...args).then(bin => {
-                if ( bin instanceof Object === false ) { return bin; }
-                // Mirror empty result as null value in order to prevent
-                // from falling back to storage.local when there is no need.
-                const tomirror = Object.assign({}, bin);
-                if ( typeof key === 'string' && Object.keys(bin).length === 0 ) {
-                    Object.assign(tomirror, { [key]: null });
-                }
-                vAPI.sessionStorage.set(tomirror);
-                return bin;
-            }).catch(reason => {
-                console.log(reason);
-            });
+        return webext.storage.local.get(key, ...args).catch(reason => {
+            console.log(reason);
         });
     },
     set(...args) {
-        vAPI.sessionStorage.set(...args);
         return webext.storage.local.set(...args).catch(reason => {
             console.log(reason);
         });
     },
     remove(...args) {
-        vAPI.sessionStorage.remove(...args);
         return webext.storage.local.remove(...args).catch(reason => {
             console.log(reason);
         });
     },
     clear(...args) {
-        vAPI.sessionStorage.clear(...args);
         return webext.storage.local.clear(...args).catch(reason => {
             console.log(reason);
         });
diff --git a/src/js/background.js b/src/js/background.js
index 123fe5778..79cae6eb1 100644
--- a/src/js/background.js
+++ b/src/js/background.js
@@ -146,7 +146,7 @@ if ( vAPI.webextFlavor.soup.has('firefox') ) {
 }
 
 const µBlock = {  // jshint ignore:line
-    wakeupReason: '',
+    alarmQueue: [],
 
     userSettingsDefault,
     userSettings: Object.assign({}, userSettingsDefault),
diff --git a/src/js/cachestorage.js b/src/js/cachestorage.js
index 056cd8b68..5dcaffbec 100644
--- a/src/js/cachestorage.js
+++ b/src/js/cachestorage.js
@@ -45,34 +45,6 @@ const keysFromGetArg = arg => {
     return Object.keys(arg);
 };
 
-// Cache API is subject to quota so we will use it only for what is key
-// performance-wise
-const shouldCache = bin => {
-    const out = {};
-    for ( const key of Object.keys(bin) ) {
-        if ( key.startsWith('cache/') ) {
-            if ( /^cache\/(compiled|selfie)\//.test(key) === false ) { continue; }
-        }
-        out[key] = bin[key];
-    }
-    return out;
-};
-
-const exGet = (api, wanted, outbin) => {
-    return api.get(wanted).then(inbin => {
-        inbin = inbin || {};
-        const found = Object.keys(inbin);
-        Object.assign(outbin, inbin);
-        if ( found.length === wanted.length ) { return; }
-        const missing = [];
-        for ( const key of wanted ) {
-            if ( outbin.hasOwnProperty(key) ) { continue; }
-            missing.push(key);
-        }
-        return missing;
-    });
-};
-
 /*******************************************************************************
  * 
  * Extension storage
@@ -83,12 +55,26 @@ const exGet = (api, wanted, outbin) => {
 
 const cacheStorage = (( ) => {
 
+    const exGet = (api, wanted, outbin) => {
+        return api.get(wanted).then(inbin => {
+            inbin = inbin || {};
+            const found = Object.keys(inbin);
+            Object.assign(outbin, inbin);
+            if ( found.length === wanted.length ) { return; }
+            const missing = [];
+            for ( const key of wanted ) {
+                if ( outbin.hasOwnProperty(key) ) { continue; }
+                missing.push(key);
+            }
+            return missing;
+        });
+    };
+
     const compress = async (bin, key, data) => {
         const µbhs = µb.hiddenSettings;
-        const isLarge = typeof data === 'string' &&
-            data.length >= µbhs.cacheStorageCompressionThreshold;
         const after = await scuo.serializeAsync(data, {
-            compress: isLarge && µbhs.cacheStorageCompression,
+            compress: µbhs.cacheStorageCompression,
+            compressThreshold: µbhs.cacheStorageCompressionThreshold,
             multithreaded: µbhs.cacheStorageMultithread,
         });
         bin[key] = after;
@@ -104,7 +90,7 @@ const cacheStorage = (( ) => {
         });
     };
 
-    return {
+    const api = {
         get(argbin) {
             const outbin = {};
             return exGet(cacheAPI, keysFromGetArg(argbin), outbin).then(wanted => {
@@ -152,7 +138,8 @@ const cacheStorage = (( ) => {
                 promises.push(compress(bin, key, keyvalStore[key]));
             }
             await Promise.all(promises);
-            cacheAPI.set(shouldCache(bin));
+            memoryStorage.set(bin);
+            cacheAPI.set(bin);
             return extensionStorage.set(bin).catch(reason => {
                 ubolog(reason);
             });
@@ -191,16 +178,18 @@ const cacheStorage = (( ) => {
             return Promise.all(toMigrate);
         },
     };
-})();
 
-// Not all platforms support getBytesInUse
-if ( extensionStorage.getBytesInUse instanceof Function ) {
-    cacheStorage.getBytesInUse = function(...args) {
-        return extensionStorage.getBytesInUse(...args).catch(reason => {
-            ubolog(reason);
-        });
-    };
-}
+    // Not all platforms support getBytesInUse
+    if ( extensionStorage.getBytesInUse instanceof Function ) {
+        api.getBytesInUse = function(...args) {
+            return extensionStorage.getBytesInUse(...args).catch(reason => {
+                ubolog(reason);
+            });
+        };
+    }
+
+    return api;
+})();
 
 /*******************************************************************************
  * 
@@ -234,6 +223,19 @@ const cacheAPI = (( ) => {
     const urlToKey = url =>
         decodeURIComponent(url.slice(urlPrefix.length));
 
+    // Cache API is subject to quota so we will use it only for what is key
+    // performance-wise
+    const shouldCache = bin => {
+        const out = {};
+        for ( const key of Object.keys(bin) ) {
+            if ( key.startsWith('cache/' ) ) {
+                if ( /^cache\/(compiled|selfie)\//.test(key) === false ) { continue; }
+            }
+            out[key] = bin[key];
+        }
+        if ( Object.keys(out).length !== 0 ) { return out; }
+    };
+
     const getOne = async key => {
         const cache = await cacheStoragePromise;
         if ( cache === null ) { return; }
@@ -327,12 +329,13 @@ const cacheAPI = (( ) => {
             ).catch(( ) => []);
         },
 
-        set(keyvalStore) {
-            const keys = Object.keys(keyvalStore);
-            if ( keys.length === 0 ) { return; }
+        async set(...args) {
+            const bin = shouldCache(...args);
+            if ( bin === undefined ) { return; }
+            const keys = Object.keys(bin);
             const promises = [];
             for ( const key of keys ) {
-                promises.push(setOne(key, keyvalStore[key]));
+                promises.push(setOne(key, bin[key]));
             }
             return Promise.all(promises);
         },
@@ -363,30 +366,46 @@ const cacheAPI = (( ) => {
  * 
  * */
 
-const memoryStorage = (( ) => {
+const memoryStorage = (( ) => {  // jshint ignore:line
 
-    const sessionStorage = webext.storage.session;
+    const sessionStorage = vAPI.sessionStorage;
+
+    // This should help speed up loading from suspended state in Firefox for
+    // Android.
+    // 20240228 Observation: Slows down loading from suspended state in
+    // Firefox desktop. Could be different in Firefox for Android.
+    const shouldCache = bin => {
+        const out = {};
+        for ( const key of Object.keys(bin) ) {
+            if ( key.startsWith('cache/compiled/') ) { continue; }
+            out[key] = bin[key];
+        }
+        if ( Object.keys(out).length !== 0 ) { return out; }
+    };
 
     return {
         get(...args) {
-            return sessionStorage.get(...args).catch(reason => {
+            return sessionStorage.get(...args).then(bin => {
+                return bin;
+            }).catch(reason => {
                 ubolog(reason);
             });
         },
 
         async keys(regex) {
-            const results = await sessionStorage.get(null).catch(( ) => {});
-            const keys = new Set(results[0]);
-            const bin = results[1] || {};
-            for ( const key of Object.keys(bin) ) {
+            const bin = await sessionStorage.get(null).catch(( ) => {});
+            const keys = [];
+            for ( const key of Object.keys(bin || {}) ) {
                 if ( regex && regex.test(key) === false ) { continue; }
-                keys.add(key);
+                keys.push(key);
             }
             return keys;
         },
 
         async set(...args) {
-            return sessionStorage.set(...args).catch(reason => {
+            const bin = shouldCache(...args);
+            if ( bin === undefined ) { return; }
+            return sessionStorage.set(bin).catch(reason => {
                 ubolog(reason);
             });
         },
@@ -522,7 +541,7 @@ const idbStorage = (( ) => {
             if ( entry.value instanceof Blob === false ) { return; }
             promises.push(decompress(keyvalStore, key, value));
         }).catch(reason => {
-            ubolog(`cacheStorage.getAllFromDb() failed: ${reason}`);
+            ubolog(`idbStorage.getAllFromDb() failed: ${reason}`);
             callback();
         });
     };
diff --git a/src/js/redirect-engine.js b/src/js/redirect-engine.js
index 7d70e35ee..1edb37624 100644
--- a/src/js/redirect-engine.js
+++ b/src/js/redirect-engine.js
@@ -72,7 +72,7 @@ const warSecret = typeof vAPI === 'object' && vAPI !== null
     : ( ) => '';
 
 const RESOURCES_SELFIE_VERSION = 7;
-const RESOURCES_SELFIE_NAME = 'compiled/redirectEngine/resources';
+const RESOURCES_SELFIE_NAME = 'selfie/redirectEngine/resources';
 
 /******************************************************************************/
 /******************************************************************************/
diff --git a/src/js/scuo-serializer.js b/src/js/scuo-serializer.js
index c0154fd9d..81b688547 100644
--- a/src/js/scuo-serializer.js
+++ b/src/js/scuo-serializer.js
@@ -281,6 +281,12 @@ const isInstanceOf = (o, s) => {
     );
 };
 
+const shouldCompress = (s, options) =>
+    options.compress === true && (
+        options.compressThreshold === undefined ||
+        options.compressThreshold <= s.length
+    );
+
 /*******************************************************************************
  * 
  * A large Uint is always a positive integer (can be zero), assumed to be
@@ -1051,10 +1057,9 @@ export const serialize = (data, options = {}) => {
     const s = writeBuffer.join('');
     writeRefs.clear();
     writeBuffer.length = 0;
-    if ( options.compress !== true ) { return s; }
+    if ( shouldCompress(s, options) === false ) { return s; }
     const lz4Util = new LZ4BlockJS();
-    const encoder = new TextEncoder();
-    const uint8ArrayBefore = encoder.encode(s);
+    const uint8ArrayBefore = textEncoder.encode(s);
     const uint8ArrayAfter = lz4Util.encode(uint8ArrayBefore, 0);
     const lz4 = {
         size: uint8ArrayBefore.length,
@@ -1145,7 +1150,6 @@ const THREAD_IAMREADY    = 2;
 const THREAD_SERIALIZE   = 3;
 const THREAD_DESERIALIZE = 4;
 
-
 class MainThread {
     constructor() {
         this.name = 'main';
diff --git a/src/js/start.js b/src/js/start.js
index 877d909c4..caa27dfbf 100644
--- a/src/js/start.js
+++ b/src/js/start.js
@@ -76,6 +76,10 @@ vAPI.app.onShutdown = ( ) => {
     permanentSwitches.reset();
 };
 
+vAPI.alarms.onAlarm.addListener(alarm => {
+    µb.alarmQueue.push(alarm.name);
+});
+
 /******************************************************************************/
 
 // This is called only once, when everything has been loaded in memory after
@@ -160,6 +164,13 @@ const onVersionReady = async lastVersion => {
         await cacheStorage.migrate(µb.hiddenSettings.cacheStorageAPI);
     }
 
+    // Remove cache items with obsolete names
+    if ( lastVersionInt < vAPI.app.intFromVersion('1.56.1b5') ) {
+        io.remove(`compiled/${µb.pslAssetKey}`);
+        io.remove('compiled/redirectEngine/resources');
+        io.remove('selfie/main');
+    }
+
     // Since built-in resources may have changed since last version, we
     // force a reload of all resources.
     redirectEngine.invalidateResourcesSelfie(io);
@@ -436,7 +447,7 @@ let selfieIsValid = false;
 try {
     selfieIsValid = await µb.selfieManager.load();
     if ( selfieIsValid === true ) {
-        ubolog(`Selfie ready ${Date.now()-vAPI.T0} ms after launch`);
+        ubolog(`Loaded filtering engine from selfie ${Date.now()-vAPI.T0} ms after launch`);
     }
 } catch (ex) {
     console.trace(ex);
@@ -506,5 +517,16 @@ ubolog(`All ready ${µb.supportStats.allReadyAfter} after launch`);
 
 µb.isReadyResolve();
 
+// Process alarm queue
+while ( µb.alarmQueue.length !== 0 ) {
+    const what = µb.alarmQueue.shift();
+    ubolog(`Processing alarm event from suspended state: '${what}'`);
+    switch ( what ) {
+    case 'createSelfie':
+        µb.selfieManager.create();
+        break;
+    }
+}
+
 // <<<<< end of async/await scope
 })();
diff --git a/src/js/static-net-filtering.js b/src/js/static-net-filtering.js
index 86d042248..01afc3a1b 100644
--- a/src/js/static-net-filtering.js
+++ b/src/js/static-net-filtering.js
@@ -4629,6 +4629,7 @@ FilterContainer.prototype.optimize = function(throttle = 0) {
 /******************************************************************************/
 
 FilterContainer.prototype.toSelfie = function() {
+    this.optimize(0);
     bidiTrieOptimize(true);
     keyvalStore.setItem('SNFE.origHNTrieContainer.trieDetails',
         origHNTrieContainer.optimize()
diff --git a/src/js/storage.js b/src/js/storage.js
index 99116547e..7c29f1422 100644
--- a/src/js/storage.js
+++ b/src/js/storage.js
@@ -1147,7 +1147,10 @@ onBroadcast(msg => {
 µb.loadRedirectResources = async function() {
     try {
         const success = await redirectEngine.resourcesFromSelfie(io);
-        if ( success === true ) { return true; }
+        if ( success === true ) {
+            ubolog('Loaded redirect/scriptlets resources from selfie');
+            return true;
+        }
 
         const fetcher = (path, options = undefined) => {
             if ( path.startsWith('/web_accessible_resources/') ) {
@@ -1220,8 +1223,11 @@ onBroadcast(msg => {
     }
 
     try {
-        const selfie = await io.fromCache(`compiled/${this.pslAssetKey}`);
-        if ( psl.fromSelfie(selfie) ) { return; }
+        const selfie = await io.fromCache(`selfie/${this.pslAssetKey}`);
+        if ( psl.fromSelfie(selfie) ) {
+            ubolog('Loaded PSL from selfie');
+            return;
+        }
     } catch (reason) {
         ubolog(reason);
     }
@@ -1235,7 +1241,8 @@ onBroadcast(msg => {
 µb.compilePublicSuffixList = function(content) {
     const psl = publicSuffixList;
     psl.parse(content, punycode.toASCII);
-    return io.toCache(`compiled/${this.pslAssetKey}`, psl.toSelfie());
+    ubolog(`Loaded PSL from ${this.pslAssetKey}`);
+    return io.toCache(`selfie/${this.pslAssetKey}`, psl.toSelfie());
 };
 
 /******************************************************************************/
@@ -1255,7 +1262,7 @@ onBroadcast(msg => {
         if ( µb.inMemoryFilters.length !== 0 ) { return; }
         if ( Object.keys(µb.availableFilterLists).length === 0 ) { return; }
         await Promise.all([
-            io.toCache('selfie/main', {
+            io.toCache('selfie/staticMain', {
                 magic: µb.systemSettings.selfieMagic,
                 availableFilterLists: µb.availableFilterLists,
             }),
@@ -1268,11 +1275,11 @@ onBroadcast(msg => {
         ]);
         lz4Codec.relinquish();
         µb.selfieIsInvalid = false;
-        ubolog(`Selfie was created`);
+        ubolog('Filtering engine selfie created');
     };
 
     const loadMain = async function() {
-        const selfie = await io.fromCache('selfie/main');
+        const selfie = await io.fromCache('selfie/staticMain');
         if ( selfie instanceof Object === false ) { return false; }
         if ( selfie.magic !== µb.systemSettings.selfieMagic ) { return false; }
         if ( selfie.availableFilterLists instanceof Object === false ) { return false; }
@@ -1300,35 +1307,26 @@ onBroadcast(msg => {
         catch (reason) {
             ubolog(reason);
         }
-        ubolog('Selfie not available');
+        ubolog('Filtering engine selfie not available');
         destroy();
         return false;
     };
 
     const destroy = function(options = {}) {
         if ( µb.selfieIsInvalid === false ) {
-            io.remove(/^selfie\//, options);
+            io.remove(/^selfie\/static/, options);
             µb.selfieIsInvalid = true;
-            ubolog('Selfie marked for invalidation');
-        }
-        if ( µb.wakeupReason === 'createSelfie' ) {
-            µb.wakeupReason = '';
-            return createTimer.offon({ sec: 27 });
+            ubolog('Filtering engine selfie marked for invalidation');
         }
         vAPI.alarms.create('createSelfie', {
-            delayInMinutes: µb.hiddenSettings.selfieAfter
+            delayInMinutes: µb.hiddenSettings.selfieAfter + 0.5
         });
         createTimer.offon({ min: µb.hiddenSettings.selfieAfter });
     };
 
     const createTimer = vAPI.defer.create(create);
 
-    vAPI.alarms.onAlarm.addListener(alarm => {
-        if ( alarm.name !== 'createSelfie') { return; }
-        µb.wakeupReason = 'createSelfie';
-    });
-
-    µb.selfieManager = { load, destroy };
+    µb.selfieManager = { load, create, destroy };
 }
 
 /******************************************************************************/