This was an idea from @herbdool in this comment but I didn't want it to get lost, so creating a separate issue to track.
WordPress provides HTML formatted emails, and it may be something our target audience really needs help with. Maybe we should look at what WP does and see if there's something simple we could do that's similar?
For reference: https://wordpress.stackexchange.com/questions/27856/is-there-a-way-to-se...
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There is a Drupal 7 contrib module that "lets the administrator see all administration pages in her preferred language" and which could be ported to Backdrop: https://www.drupal.org/project/...
Allow admin to select admin language seperate from front end language (multilingual)
@stpaultim – You're right: my approach affects also the main menu. I guess, because menus are also considered as user interface (not as content). @findlabnet – If I didn't miss anything,...
Allow admin to select admin language seperate from front end language (multilingual)
Go to the account edit of the desired user. On the horizontal tab below "Region and Language," select "English" or another language. WFM.
Allow admin to select admin language seperate from front end language (multilingual)