diff --git a/chrome/show_toolbars_in_popup_windows.css b/chrome/show_toolbars_in_popup_windows.css
new file mode 100644
index 0000000..b9a5b2e
--- /dev/null
+++ b/chrome/show_toolbars_in_popup_windows.css
@@ -0,0 +1,5 @@
+/* Source file https://github.com/MrOtherGuy/firefox-csshacks/tree/master/chrome/show_toolbars_in_popup_windows.css made available under Mozilla Public License v. 2.0
+See the above repository for updates as well as full license text. */
+
+:root[chromehidden~="toolbar"] :is(.browser-toolbar,.chromeclass-toolbar-additional) { display: -moz-box }
+:root[chromehidden~="toolbar"] .browser-toolbar { visibility: visible }
\ No newline at end of file
diff --git a/html_resources/tagmap.json b/html_resources/tagmap.json
index a8eb969..0c9c2e0 100644
--- a/html_resources/tagmap.json
+++ b/html_resources/tagmap.json
@@ -110,5 +110,6 @@
 "curved_tabs.css":["tabs","tab"],
 "theme_aware_modal_prompts.css":["effect","dark-mode","colors","popup"],
 "centered_top_statuspanel.css":["status"],
-"custom_menupopup_check_icons.css":["icon","menu","minimal","popup"]
+"custom_menupopup_check_icons.css":["icon","menu","minimal","popup"],
+"show_toolbars_in_popup_windows.css":["toolbars","popup"]
 }
diff --git a/tags.csv b/tags.csv
index 81a4316..0496940 100644
--- a/tags.csv
+++ b/tags.csv
@@ -110,3 +110,4 @@ curved_tabs.css,tabs,tab
 theme_aware_modal_prompts.css,effect,dark-mode,colors,popup
 centered_top_statuspanel.css,status
 custom_menupopup_check_icons.css,icon,menu,minimal,popup
+show_toolbars_in_popup_windows.css,toolbars,popup