It it possible to make this extension work with the Flatpak version of web browsers?

[linlinxza]

Hi,

I love this extension. But there's an issue. I am trying to migrate over to the Flatpak version of LibreWolf. Is there a way you can make this extension work with Flatpak versions of the web browsers?

[pxmqsbqc]

I'd like too to view this extension work in Flatpak browsers!

Maybe is it possible throught flatpak-spawn?

[omega3]

I also wanted it to work with Firefox installed via flatpak. I also installed mpv via flatpak. And I have installed NodeJS in host but also for user from script and moved files to corresponding folders in
/home/user/.var/app/org.mozilla.firefox/

I followed this
[PRE_SCRIPT] return undefined in Firefox · Issue #82 · andy-portmen/external-application-button
#82

Here are my settings in options:
Display Name: Display Name
Executable Name:
/usr/bin/flatpak run --branch=stable --arch=x86_64 --command=mpv --file-forwarding io.mpv.Mpv --player-operation-mode=pseudo-gui -- @@u %U @@
Arguments:
--ytdl --http-header-fields="Referer: [PRE_SCRIPT]" [HREF]
Pre JavaScript:
document.currentScript.output = location.href

Toolbar button and Link Context checked. And "Cannot find the native client" appears. What is wrong and what else can I check?