How I got to this? By asking Google "Thunderbird edit reply in external editor", then I've followed the bread crumbs:<p>=> <<a href="https://bugzilla.mozilla.org/show_bug.cgi?id=259633" rel="nofollow">https://bugzilla.mozilla.org/show_bug.cgi?id=259633</a>> (18 years old), duplicate of,<p>=> <<a href="https://bugzilla.mozilla.org/show_bug.cgi?id=241583" rel="nofollow">https://bugzilla.mozilla.org/show_bug.cgi?id=241583</a>> (18 years old), duplicate of,<p>=> <<a href="https://bugzilla.mozilla.org/show_bug.cgi?id=13474" rel="nofollow">https://bugzilla.mozilla.org/show_bug.cgi?id=13474</a>> (23 years old), bug still open...<p>BTW, I used to use `It's all text`, the Firefox addon that allowed one to edit text-areas in external editors, but it broke a few years ago... (Coincidentally or not, that was the time I've also dropped using MoinMoin and other wikis... Also coincidence or not, that was the time I've started using Chromium more...)<p>The other recommended addon is `exteditor`, but it seems that, just like `It's all text`, it also doesn't work in latest Thunderbird: <<a href="https://github.com/exteditor/exteditor/issues/74" rel="nofollow">https://github.com/exteditor/exteditor/issues/74</a>>...<p>Is it that hard to ask, in 2022 when we have so many good text editors, to be able to use one instead of the built-in ones?<p>Perhaps nobody wants this feature? Searching the Mozilla Bugzilla instance shows another story...