Yes - it is 58058. Here is the forum thread also: Web App language problem - #3 by SteveP.
As you will see, it is indeed fixed in 2020R1 but (for me and others) makes staying on the suggested fallback of 19r3.1 or 3.2 not possible therefore (and I haven’t even trawled over the release notes to determine an implication) falling back further to 19r1.1 IF localisation is important until such time that the conversion to 2.0 is practical.
Steve
EDIT: Thought I did a ‘Reply To’ but apparently not, so tagging you @Geoff_Perlman instead