The WebExtension allows switching tabs with CTRL+[1-9] without disabling ALT+[1-9]. (only useful for Linux users) Source:

What is shortcuts?
Shortcuts is a Firefox add-on that enables quick tab switching in Firefox for Linux users. It allows you to use CTRL+[1-9] to switch tabs without disabling ALT+[1-9]. Enhance your tab navigation experience with Shortcuts.
By: SqYtCO
Users: 124 ▲ 4
Rating: 4.60 (5)
Version: 1.0.1 (Last updated: 2018-01-14)
Creation date: 2018-01-14
Weekly download count: 3
Firefox on Android: Yes
Risk impact: Moderate risk impact
Risk likelihood: Low risk likelihood
Manifest version: 2
  • tabs
  • activeTab
Size: 5.52K
Stats date:

Other platforms

Not available on Chrome
Not available on Edge
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User reviews
I just want to disable alt+[1-9]. It is stopping me using the special chars on my number keys and only Firefox has this issue, everything else in the world works perfectly and even allows you to customer shortcuts. 1990's firefox,
by RLW, 2023-06-17
View all user reviews
Risk impact

shortcuts may not be safe to use and it requires some risky permissions. Exercise caution when installing this add-on. Review carefully before installing.

Risk likelihood

shortcuts has earned a fairly good reputation and likely can be trusted.

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