Are most of the existing add-ons being sacrificed due to adding support for WebExtension?

Eric Moore emoore at
Wed Nov 22 15:45:57 UTC 2017

"No one has made any decision, the facts are imposed on us by changes in
Mozilla-core. All people actively involved with the development of TB
were aware of the never-ending bustage coming in from Mozilla-core."

Thank you for your detailed reply.

I had followed the earlier discussions about whether or not to fork in 
the tb-planning mailing list, and had been left with the impression that 
a distinction was made between forking Gecko as a long term solution, 
and temporarily deciding not to use the version 57 and 59's toolkit 
while trying to develop Thunderbird++ as soon as possible.

My concern is that there is a serious disconnect with what users want 
and expect. They are not expecting most of the add-ons to break. My 
impression is that they expect Thunderbird to somehow avoid following 
the path Firefox took. There is also a lot of concern about the future 
of Thunderbird. Many are well aware of Thunderbird's problems, but 
nobody is telling them what to expect, or offering them any hope. There 
is just silence.

I'm seeing more users decide not to upgrade to the latest version in 
order to keep their favorite add-ons working. I suspect many would be 
comfortable temporarily living with the potential risks of a out of date 
toolkit if that is what it takes to not lose most add-ons. Especially 
those that select "view -> display attachments inline".

What troubles me is if a decision was made by "the Council, the 
Engineering Steering Committee and the developer community" why wasn't a 
post made about it on the Thunderbird blog explaining what they are 
thinking of doing, why its necessary, and what the implications are. 
Especially "If we determine the only viable path forward is to frame 
everything in an embedded WebExtension, we might consider automating 
this change for all Thunderbird add-ons." (from Philipp's post).

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