App Tab Cleaner od babs42

Clicking a meeting, chat or notes link often opens the desktop app, and leaves a useless browser tab behind. App Tab Cleaner closes those tabs for you a few seconds after the app takes over.

HOW IT WORKS
• When a tab opens, navigates to or reloads a URL matching one of your rules, a countdown starts on the toolbar button (10 seconds by default).
• When it reaches zero, the tab closes. If it was the last tab in the window, a new tab opens in its place so the window stays open.
• Changed your mind? Click "Keep this tab" in the popup, or navigate the tab somewhere else, and it stays open.
• Tip: pin the button to your toolbar from the extensions menu to see the countdown, or turn on "Notify before closing" in the settings.

WORKS OUT OF THE BOX
Built-in rules recognise the "handoff" pages that popular video-meeting, chat, notes, community and project-management apps leave behind, not their normal web versions. You can edit, reorder or turn off any of them.
Rules for apps whose handoff pages look identical to normal use are included but off by default.

YOUR OWN RULES
• Match any URL with regular expressions, with optional exceptions
• Set a timeout per rule, from 0 seconds to an hour
• Test patterns against a URL live in the rule editor
• Drag to reorder rules; the first match wins
• Pause everything with one switch
• Import and export rules as JSON
• Rules sync between your Firefox installs through Firefox Sync

PRIVACY
App Tab Cleaner collects nothing and makes no network requests. It has no host permissions, no content scripts, and never reads page content. It uses only:
• tabs: to read tab URLs and close matching tabs
• storage: to save your rules
• alarms: to close tabs reliably after long timeouts
• notifications (optional): only if you turn on "Notify before closing"

Free and open source (MIT): https://github.com/babraham123/app-tab-cleaner