I am developing my first Firefox extension using Webextensions. When using “Load a temporary add-on” locally on my computer, everything runs fine. However, on the published version (https://addons.mozilla.org/en-US/firefox/addon/youtube-caption-indicator/) nothing seems to work: the add-on is supposed to add some information to YouTube search results and I don’t see any. I tried to follow Mozilla’s add-on debugging instructions, but all I get is an empty Debugger tab:
https://i.stack.imgur.com/s01ZN.png
I probably do something obviously wrong, any ideas ?