Developer reply by Jonathan Kamens
Rated 5 out of 5 stars
Make it possible to use this add-on for a variety of emails. For example, in the list of emails. For 5 selected emails - apply the "Send within a week" function (or others).
Another note - TB is slowing down a lot because of this add-on (~ 150 messages are planned).
I've created a ticket for your suggestion at https://github.com/Extended-Thunder/send-later/issues/585 . It's a reasonable idea, though I'm not sure when we'll get to it. You should know that you can use the Mail Merge add-on to schedule multiple form letters with Send Later.
Regarding the speed problem, this should be addressed in the current version, but if not, then you should make sure that all of your Drafts folders are configured for offline synchronization; I think that will speed things up considerably.
EDITED 2023-08-25 to add: This feature is implemented in the new pre-release / beta version of the add-on. See https://github.com/Extended-Thunder/send-later/releases/tag/v10.0.6 . Please try it out and send feedback to send-later-support@extended-thunder.org !
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