Tab Volume Slider от EvilDuck Tools

Tab Volume Slider adds a simple volume control to Firefox that works on a per-tab basis.

Click the pinned toolbar icon to adjust the audio level for the current tab without affecting other tabs or system volume. The slider applies to audio and video elements on the page, including most embedded players and iframes.

Features:
• Per-tab volume control
• Mute toggle with restore
• Automatic re-apply on page reload
• Works with embedded media and iframes
• No tracking, no analytics, no network requests

All settings are stored locally and never leave your device.