I wonder if "1.30+" is correct. I'm still using MW 1.31 (I do intend to upgrade soon). I used git to change Widgets from REL1_31 to master (because of the security warning) and it broke my site. Instead of looking into it, I've just gone back to REL1_31, but I just thought I'd note it here. Jonathan3 (talk) 19:42, 29 March 2020 (UTC)
Topic on Extension talk:Widgets
You are right. I should say 1.31+ since everything earlier is no longer supported due to the security issue. Theoretically you could still use the "latest" 1.3.0 release for earlier versions but this will be hazardous. REL1_31 works fine with MW 1.31.x and was supplied with the security fix.
Ok, the info on the page was not really good. Just updated it to make it clear. Thanks for asking!