Development

Topic	Replies	Views	Activity
Get started with Firefox extension development Extensions provide a simple and powerful way to personalize your browsing experience. If you know JavaScript, CSS, and HTML, you can build your own. If you are brand-new to add-on development, you can get started by che…	6	16165	September 30, 2025
About the Development category	0	4514	May 21, 2015
Insert text into textbox with add-on click learning	0	3	December 12, 2025
Is Firefox MV3 intentionally not supporting `browser.runtime.onMessage` in MV3 userScripts API? Why?	2	32	December 10, 2025
How to prevent redirecting to HTTPS when fetching local address from a background script?	2	23	December 3, 2025
Do older Firefox versions ignore "data_collection_permissions"?	2	144	December 3, 2025
A way to set tab context as default for new tab	3	68	November 18, 2025
[EDITED] Error: Permission denied to access property "then" issue , manifest-v3	4	2150	November 18, 2025
Funcions `loadOneTab` and `loadURI` in 2023 in Firefox Experimental API?	2	686	November 16, 2025
Foucs behavior issue on sidebar when opening	1	26	October 29, 2025
Pin Tab Enhancement / Side Bar Control	2	299	October 25, 2025
[Manifest V3] background script stopped when signed extension is up	3	61	October 15, 2025
WebExtension API support for web app windows	3	88	October 10, 2025
IDEA - Add Unsubscribe Footer thunderbird	0	36	October 5, 2025
Validation says data_collection_permissions missing, but exists in manifest? issue	2	512	September 20, 2025
Do extension settings reference or depend on the extension's internal uuid?	2	28	September 19, 2025
Can we access location of new tab wallpaper?	2	42	September 15, 2025
License: This field, or custom_license, is required for listed versions	3	71	September 12, 2025
Error when use web-ext with chrome with `--keep-profile-changes`? issue	3	71	August 29, 2025
How to restore a recently-closed tab group via WebExtensions API	2	212	August 28, 2025
Does web-ext not load extension when use with Chrome? learning , issue	3	51	August 28, 2025
WebExtError when signing but still succeed? issue	1	37	August 25, 2025
What happens to storage when a user updates the extension? updates	1	49	August 17, 2025
Accessing closed tab groups	4	216	August 11, 2025
Deleting All Bookmarks in Folder (weird Fx bug?)	8	108	August 8, 2025
Any idea to create new window in correct position in 3200x2000 with 200% scale?	3	48	August 6, 2025
Where did `firefox-storage-test.glitch.me` go?	2	65	August 5, 2025
scripting.messageDisplay.registerScripts() are called twice?	5	77	August 5, 2025
How do you get type hinting for webext APIs in VSCode without using bundlers?	5	869	July 25, 2025
Dynamically adding elements to the updated sidebar	1	60	July 22, 2025

Get started with Firefox extension development

Extensions provide a simple and powerful way to personalize your browsing experience. If you know JavaScript, CSS, and HTML, you can build your own. If you are brand-new to add-on development, you can get started by che…