--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -482,16 +482,19 @@ pref("browser.tabs.restorebutton", 0);
 // true   return to the tab that opened this tab (its owner)
 // false  return to the adjacent tab (old default)
 pref("browser.tabs.selectOwnerOnClose", true);
 
 pref("browser.tabs.showAudioPlayingIcon", true);
 // This should match Chromium's audio indicator delay.
 pref("browser.tabs.delayHidingAudioPlayingIconMS", 3000);
 
+// The minimum tab width in pixels
+pref("browser.tabs.tabMinWidth", 50);
+
 pref("browser.ctrlTab.previews", false);
 
 // By default, do not export HTML at shutdown.
 // If true, at shutdown the bookmarks in your menu and toolbar will
 // be exported as HTML to the bookmarks.html file.
 pref("browser.bookmarks.autoExportHTML",          false);
 
 // The maximum number of daily bookmark backups to

--- a/browser/base/content/browser.css
+++ b/browser/base/content/browser.css
@@ -5,16 +5,17 @@
 @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
 @namespace html url("http://www.w3.org/1999/xhtml");
 
 :root {
   --panelui-subview-transition-duration: 150ms;
   --lwt-additional-images: none;
   --lwt-background-alignment: right top;
   --lwt-background-tiling: no-repeat;
+  --tab-min-width: 50px;
 }
 
 :root:-moz-lwtheme {
   color: var(--lwt-text-color) !important;
 }
 
 :root:-moz-lwtheme {
   background-color: var(--lwt-accent-color) !important;
@@ -127,17 +128,17 @@ tabbrowser {
 
 .tabbrowser-tab {
   -moz-binding: url("chrome://browser/content/tabbrowser.xml#tabbrowser-tab");
 }
 
 .tabbrowser-tab:not([pinned]) {
   -moz-box-flex: 100;
   max-width: 225px;
-  min-width: 100px;
+  min-width: var(--tab-min-width);
   width: 0;
   transition: min-width 100ms ease-out,
               max-width 100ms ease-out;
 }
 
 .tabbrowser-tab:not([pinned]):not([fadein]) {
   max-width: 0.1px;
   min-width: 0.1px;

--- a/browser/base/content/tabbrowser.xml
+++ b/browser/base/content/tabbrowser.xml
@@ -5809,16 +5809,25 @@
               // This is the only pref observed.
               this._findAsYouType = Services.prefs.getBoolPref("accessibility.typeaheadfind");
               break;
             }
           }
         ]]></body>
       </method>
 
+      <field name="_tabMinWidthLimit">50</field>
+      <property name="tabMinWidth">
+        <setter><![CDATA[
+          let root = document.documentElement;
+          root.style.setProperty("--tab-min-width", val + "px");
+          return val;
+        ]]></setter>
+      </property>
+
       <constructor>
         <![CDATA[
           this.mCurrentBrowser = document.getAnonymousElementByAttribute(this, "anonid", "initialBrowser");
           this.mCurrentBrowser.permanentKey = {};
 
           Services.obs.addObserver(this, "contextual-identity-updated");
 
           this.mCurrentTab = this.tabContainer.firstChild;
@@ -5899,16 +5908,23 @@
           XPCOMUtils.defineLazyPreferenceGetter(this, "animationsEnabled",
                                                 "toolkit.cosmeticAnimations.enabled", true);
           XPCOMUtils.defineLazyPreferenceGetter(this, "tabWarmingEnabled",
                                                 "browser.tabs.remote.warmup.enabled", false);
           XPCOMUtils.defineLazyPreferenceGetter(this, "tabWarmingMax",
                                                 "browser.tabs.remote.warmup.maxTabs", 3);
           XPCOMUtils.defineLazyPreferenceGetter(this, "tabWarmingUnloadDelay" /* ms */,
                                                 "browser.tabs.remote.warmup.unloadDelayMs", 2000);
+          XPCOMUtils.defineLazyPreferenceGetter(this, "tabMinWidthPref",
+                                                "browser.tabs.tabMinWidth", this._tabMinWidthLimit,
+            (pref, prevValue, newValue) => this.tabMinWidth = newValue,
+            newValue => Math.max(newValue, this._tabMinWidthLimit),
+          );
+
+          this.tabMinWidth = this.tabMinWidthPref;
         ]]>
       </constructor>
 
       <method name="_generateUniquePanelID">
         <body><![CDATA[
           if (!this._uniquePanelIDCounter) {
             this._uniquePanelIDCounter = 0;
           }