diff --git a/app/common/setting-definitions.js b/app/common/setting-definitions.js
index 8638960..1d0cfe6 100644
--- a/app/common/setting-definitions.js
+++ b/app/common/setting-definitions.js
@@ -25,6 +25,15 @@ let _VAL = { __proto__: null };
 /// The default validator for bool values
 let _vbool = (v)=>{ return ((typeof v === 'boolean')?v:undefined)};
 
+/// The default validator for integer values
+let _vint = (v)=>{
+    const num = Number(v);
+    if(isNaN(num) || (Math.trunc(num) != num)) {
+        return undefined;
+    }
+    return num;
+};
+
 // Booleans {{{2
 _NAM.CFG_POPUP_ON_STARTUP = 'open-popup-on-chrome-startup';
 _DEF[_NAM.CFG_POPUP_ON_STARTUP] = true;
@@ -165,6 +174,12 @@ _VAL[_NAM.CFGS_FAVICON_SOURCE] = (v)=>{
     return (( v === FAVICON_SITE || v === FAVICON_CHROME || v === FAVICON_DDG ) ? v : undefined);
 };
 
+// #316.  How often to autoremember.  Empty or <= 0 == don't autosave
+_NAM.CFGS_AUTOREMEMBER_MINUTES = 'autoremember-timer-minutes';
+_DEF[_NAM.CFGS_AUTOREMEMBER_MINUTES] = '';
+_VAL[_NAM.CFGS_AUTOREMEMBER_MINUTES] = _vint;
+
+
 // }}}2
 
 /// The default values for the configuration settings.
@@ -238,6 +253,33 @@ function getBoolSetting(setting_name, default_value = undefined)
     }
 } //getBoolSetting
 
+/// Get an integer setting from the settings page.
+/// @param setting_name     A value in CFG_NAMES
+/// @param default_value    Optional default.  If unspecified or
+///                         undefined, the default from CFG_DEFAULTS
+///                         is used.
+function getIntSetting(setting_name, default_value = undefined)
+{
+    if(typeof default_value === 'undefined' && setting_name in CFG_DEFAULTS) {
+        default_value = CFG_DEFAULTS[setting_name];
+    }
+
+    let locStorageValue = localStorage.getItem(SETTING_PREFIX + setting_name);
+
+    if ( locStorageValue === null ) {   // nonexistent key
+        return default_value;
+    } else {
+        const str = String(locStorageValue);
+        let val = JSON.parse(locStorageValue);  // stored with double-quotes
+        val = _vint(val);
+        if (typeof val === 'undefined') {
+            return default_value;
+        } else {
+            return val;
+        }
+    }
+} //getIntSetting
+
 /// Find out whether the given setting from the settings page exists.
 /// @param setting_name     A value in CFG_NAMES
 function haveSetting(setting_name)
@@ -302,6 +344,7 @@ let me = {
     getRaw: getRawSetting,
     getString: getStringSetting,
     getBool: getBoolSetting,
+    getInt: getIntSetting,
     have: haveSetting,
     set: setSetting,
     setIfNonexistent: setSettingIfNonexistent,
diff --git a/app/settings/manifest.js b/app/settings/manifest.js
index 7c8e478..04fbe2b 100644
--- a/app/settings/manifest.js
+++ b/app/settings/manifest.js
@@ -216,6 +216,15 @@ setting_definitions.push(
             "type": "checkbox",
             "label": future_i18n('Prompt for confirmation before closing or deleting a tab that is currently playing audio (<i class="fa fa-music"></i>)'),
         },
+        {
+            "tab": future_i18n("Behaviour"),
+            "group": future_i18n("Autoremember"),
+            "name": S.S_AUTOREMEMBER_MINUTES,
+            "type": "text",
+            "label": future_i18n('If this is an integer <tt>I</tt> &gt;= 0, automatically '
+                + 'remember all open windows/tabs every <tt>I</tt> minutes.  Refresh the '
+                + 'TabFern window to apply changes to this option.'),
+        },
 
         // Appearance
         {
@@ -489,7 +498,16 @@ setting_definitions.push(
             'group_html':true,
             "type": "description",
             "text": (
-`<ul>
+`<h4>TF needs developers!</h4>
+<p>As you've noticed, my time to work on TabFern is limited 😅 .
+If you are a JavaScript developer, could you contribute some code?  I'm happy
+to help you get started!  If you aren't a JS dev, but know someone who is,
+could you please pass the word?  Much appreciated!
+</p>
+<ul>
+<li>TabFern can now automatically mark windows as remembered on a timer.
+    Set the timer you want in ${settings} Behaviour ${gt} Autoremember
+    ${issue(316)}.</li>
 <li>The prompt for confirmation when closing audible tabs now applies to
     individual tabs ${issue(306)}.</li>
 <li>Bugfixes ${issue(322)}</li>
diff --git a/app/win/main_tl.js b/app/win/main_tl.js
index 3b43a3d..e3974f5 100644
--- a/app/win/main_tl.js
+++ b/app/win/main_tl.js
@@ -4301,6 +4301,50 @@ function addEventListeners(done)
     done();
 } //addEventListeners
 
+// Mark all windows as remembered
+function rememberAll()
+{
+    var modified = false;
+    L.log.info('Marking all windows as remembered')
+    try {
+        const root = T.treeobj.get_node($.jstree.root);
+        root.children.forEach( (kid_node_id, kid_idx)=>{
+            const val = D.windows.by_node_id(kid_node_id);
+            if(val && (val.keep !== K.WIN_KEEP)) {
+                modified = true;
+                M.remember(kid_node_id);
+            }
+        });
+
+    } catch(e) {
+        log.warn({'Failure when trying to auto-remember windows': e})
+        // But don't throw the error since we still want to save the tree.
+    }
+
+    if(modified) {
+        saveTree();
+    }
+} //rememberAll
+
+// Timer handler to call rememberAll() and set the next timer.
+function autoRememberAll(minutes, only_start_timer = false)
+{
+    if(!only_start_timer) {
+        rememberAll();
+    }
+
+    L.log.info(`Starting autoremember timer for ${minutes} minute(s)`);
+    window.setTimeout(()=>{autoRememberAll(minutes)}, minutes*60*1000);
+} // autoRememberAll
+
+function startAutoRememberTimerIfRequested(done) {
+    const minutes = S.getInt(S.S_AUTOREMEMBER_MINUTES, 0);
+    if(minutes > 0) {
+        autoRememberAll(minutes, true);  // true => just start the timer
+    }
+    done();
+} // startAutoRememberTimerIfRequested()
+
 /// The last function to be called after all other initialization has
 /// completed successfully.
 function initTreeFinal(done)
@@ -4410,6 +4454,8 @@ function main()
     };
     //let spin_timer = window.setTimeout(spin_starter, 1000);
 
+    // --- Init steps ---
+
     s.then(determine_devel_mode)
     .then(basicInit)
 
@@ -4439,9 +4485,11 @@ function main()
     })
     .then(addOpenWindowsToTree)
     .then(addEventListeners)
-    .then(initTreeFinal)
+    .then(initTreeFinal)        // This needs to be the last real init step
+
+    .val(check_init_step_count) // This is a sanity check after initTreeFinal
 
-    .val(check_init_step_count)
+    // --- Post-init steps ---
 
     // Stop the spinner, if it started
     .val(()=>{
@@ -4450,6 +4498,11 @@ function main()
         //clearTimeout(spin_timer);
     })
 
+    // Start the autoremember timer now that all the state is consistent
+    .then(startAutoRememberTimerIfRequested)
+
+    // --- Error handling ---
+
     .or((err)=>{
         $(K.INIT_MSG_SEL).text(
             $(K.INIT_MSG_SEL).text() + "\n" + err