This add-on (Audio Equalizer) prevents playback of any video thumbnail that doesn't have audio especially in less popular websites. This can be easily ascertained by simply disabling the add-on (Audio Equalizer) and seeing the problem disappear.

While in private mode with nothing but this add-on (Audio Equalizer) enabled and after the page is fully loaded. Bringing the cursor/touch pointer to a standstill over an 'image' thumbnail will trigger the fetching and playback of 'video' thumbnail.

Afterwards in the developer console (F12) we see the following warning (Yellow Background) generated immediately:

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An AudioContext was prevented from starting automatically. It must be created or resumed after a user gesture on the page.
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I would like to point out that I have had already changed the Autoplay permission in Firefox's privacy setting page (about:preferences#privacy) for all websites from 'Block Audio' to 'Allow Audio and Video' Before Installing this add-on (Audio Equalizer).

Above warning is then immediately followed by the error (Red Background) below:

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Uncaught (in promise) DOMException: The fetching process for the media resource was aborted by the user agent at the user's request. inject.js:97

attach moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:97
attach moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:86
moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:135
EventListener.handleEvent* moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:133

attach moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:97
forEach self-hosted:160
attach moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:86
moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:135
(Async: EventListener.handleEvent)
moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js:133
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I tried to use the ON/OFF button in the add-on (Audio Equalizer) from its own popup so that the add-on (Audio Equalizer) remains enabled in Firefox but doesn't try to inject the following script which is the source of error ( into the page:

moz-extension://[ADDON-UUID]/data/content_script/page_context/inject.js

However probably thanks to Audio Equalizer's 'Access your data for all websites' permission, Unless you disable the add-on (Audio Equalizer) from inside the Firefox's add-on page (about:addons) the script will still get injected and thus no video thumbnail playback.

I even tried adding 'moz-extension://[ADDON-UUID]' to uBlock Origin's "My filters" and "My rules" tabs based on each tab's correct syntax while removing 'moz-extension-scheme' from "Trusted sites", nevertheless Firefox would still inject the script into the website so long as the add-on was enabled despite "ON/OFF" button being gray (presumably indicating an 'off' state) rather than black (presumably indicating an 'on' state) according to its own popup menu.

As it's not properly programmed to handle audio-less videos and there is no way included to prevent itself from activating on user-defined specified websites (say by actually having an options tab that comes with a configurable exclusion list inside add-on's Firefox page rather than its popup with its ineffective "ON/OFF" button); I believe that the badge granted to this add-on by Mozilla Foundation is without merit and should be revoked.

After all the following is a direct quote from hovering over the badge of each add-on recommended by Mozilla Foundation:
"Firefox only recommends extensions that meet our standards for security and performance"

Hello,
a useful add-on that significantly improves the sound, no matter what sound device you use.
Thank you for that.
Unfortunately it doesn't work as hoped on a website I use often. The sound is switched off completely.
Even with the equalizer deactivated there is no sound:
> http://radio.garden/ <
I would be very grateful for a short explanation.
Best regards
Edit:
Hello again, I was able to solve my problem myself. Simply add the website to the whitelist in the Firefox context menu. 👌
Thanks again

ON/OFF switch often does NOT work, use preamp to 65%-70%, above u get compression distortions. Overall good EQ, if not spy app. Cheers :)

Extension keeps a power request alive in Windows even after video/audio has stopped, preventing the system from sleeping and automatic shutdown.

where is it even located?? after install, its nowhere to be found, so it cannot even be used.

Awesome add-on though it prevents Tiktok videos from playing. Otherwise 100% perfect.

Just the extension I needed, I just moved from another browser, and that was an essential because most of the times I'm hearing music, and it can get really loud or really low the volume in some videos. THANK YOU!

Незаменимая вещь для меня!

I love it! This brings back old memories of days gone by when stereo systems were quality made, speakers were 4 feet tall and the system included an equalizer so you could adjust your setting to hear the quality of the music, unlike the tiny gadgets that come out of china now days that are about the size of a tuna can, and your only option is a tinny sound that is similar to fingernails on a chalkboard.

doesn't work with Spotify's web player

Works like a charm! Tested on YouTube Music.

keren

It is an equalizer, that works for the browser that is being used. I liked it.

Doesn't work on all websites with audio playing, seemingly inconsistent if/when it wants to work at all on some sites.