I’m not a developer. Apologies if I’ve missed or misunderstood something.
Some developers may be in the process of porting their extensions. My understanding is that in order to port their addon’s data from legacy to webextension they will need to be hybrid for at least one version [of their addon].
Doesn’t this mean that in most legacy-to-webextension situations the developer is likely to hold off switching to a full webextension version until the last possible moment (the end of 56) to ensure that as many of their users are updated?
Perhaps it would be good to get a good poll of developers who intend to port for 57. Notably this would prevent us from recommending webextensions for them.
Or at least, deprioritize finding (or creating?) alternatives (in case they didn’t come through in time).