--- a/browser/base/content/browser.css
+++ b/browser/base/content/browser.css
@@ -697,17 +697,17 @@ toolbar:not(#TabsToolbar) > #personal-bo
 /* Define the minimum width based on the style of result rows.
    The order of the min-width rules below must be in increasing order. */
 #PopupAutoComplete[resultstyles~="loginsFooter"],
 #PopupAutoComplete[resultstyles~="insecureWarning"] {
   min-width: 17em;
 }
 
 #PopupAutoComplete[resultstyles~="generatedPassword"] {
-  min-width: 21em;
+  min-width: 22em;
 }
 
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="insecureWarning"] {
   height: auto;
 }
 
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="loginWithOrigin"] > .ac-site-icon,
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="insecureWarning"] > .ac-site-icon {

--- a/browser/themes/shared/autocomplete.inc.css
+++ b/browser/themes/shared/autocomplete.inc.css
@@ -96,21 +96,25 @@
 }
 
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="generatedPassword"] {
   /* Workaround bug 451997 and/or bug 492645 */
   display: block;
 }
 
 
-#PopupAutoComplete > richlistbox > richlistitem[originaltype="generatedPassword"] > .two-line-wrapper > .labels-wrapper > .line2-label {
+#PopupAutoComplete > richlistbox > richlistitem[originaltype="generatedPassword"] > .two-line-wrapper > .labels-wrapper > .line2-label > span {
+  /* The font-family is only adjusted on the inner span so that the
+     line-height of .line2-label matches that of .line1-label */
   font-family: monospace;
 }
 
-#PopupAutoComplete > richlistbox > richlistitem[originaltype="generatedPassword"] > .two-line-wrapper > .labels-wrapper > .generated-password-autosave {
+#PopupAutoComplete > richlistbox > richlistitem[originaltype="generatedPassword"] > .two-line-wrapper > .labels-wrapper > .generated-password-autosave > span {
+  /* The font-* properties are only adjusted on the inner span so that the
+     line-height of .generated-password-autosave matches that of .line1-label */
   font-style: italic;
   font-size: 0.85em;
   white-space: normal;
 }
 
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="login"] + richlistitem[originaltype="generatedPassword"],
 #PopupAutoComplete > richlistbox > richlistitem[originaltype="loginWithOrigin"] + richlistitem[originaltype="generatedPassword"] {
   /* Separator between logins and generated passwords. This uses --panel-separator-color from default

--- a/toolkit/content/widgets/autocomplete-richlistitem.js
+++ b/toolkit/content/widgets/autocomplete-richlistitem.js
@@ -718,18 +718,25 @@
       this.querySelector(".line2-label").textContent = details.comment;
     }
   }
 
   class MozAutocompleteGeneratedPasswordRichlistitem extends MozAutocompleteTwoLineRichlistitem {
     constructor() {
       super();
 
+      // Line 2 and line 3 both display text with a different line-height than
+      // line 1 but we want the line-height to be the same so we wrap the text
+      // in <span> and only adjust the line-height via font CSS properties on them.
+      this.generatedPasswordText = document.createElement("span");
+
+      this.line3Text = document.createElement("span");
       this.line3 = document.createElement("div");
       this.line3.className = "label-row generated-password-autosave";
+      this.line3.append(this.line3Text);
     }
 
     get _autoSaveString() {
       if (!this.__autoSaveString) {
         let brandShorterName = Services.strings
           .createBundle("chrome://branding/locale/brand.properties")
           .GetStringFromName("brandShorterName");
         this.__autoSaveString = Services.strings
@@ -740,22 +747,27 @@
       }
       return this.__autoSaveString;
     }
 
     _adjustAcItem() {
       let { generatedPassword, willAutoSaveGeneratedPassword } = JSON.parse(
         this.getAttribute("ac-label")
       );
-      this.querySelector(".line2-label").textContent = generatedPassword;
+      let line2Label = this.querySelector(".line2-label");
+      line2Label.textContent = "";
+      this.generatedPasswordText.textContent = generatedPassword;
+      line2Label.append(this.generatedPasswordText);
 
-      this.line3.textContent = willAutoSaveGeneratedPassword
-        ? this._autoSaveString
-        : "";
-      this.querySelector(".labels-wrapper").append(this.line3);
+      if (willAutoSaveGeneratedPassword) {
+        this.line3Text.textContent = this._autoSaveString;
+        this.querySelector(".labels-wrapper").append(this.line3);
+      } else {
+        this.line3.remove();
+      }
 
       super._adjustAcItem();
     }
   }
 
   customElements.define(
     "autocomplete-richlistitem",
     MozElements.MozAutocompleteRichlistitem,