https://bugs.winehq.org/show_bug.cgi?id=48006
--- Comment #42 from Andrew Church achurch+wine@achurch.org --- Turns out the Proton issue was a PEBKAC, installed it into a different location than I intended. Proton 9.0-beta15 does in fact get the launcher to work.
(In reply to Gabriel Ivăncescu from comment #41)
How does the last error look like?
02b0:trace:jscript:throw_error 800a13d6 02b0:trace:jscript:DispatchEx_Release (000000000B7165E0) ref=5 02b0:trace:jscript:DispatchEx_Release (000000000AE8CEC0) ref=6 02b0:warn:jscript:unwind_exception Exception 80020009 undefined in: 02b0:warn:jscript:print_backtrace 0 000000000B5744A0->[unnamed](L"t"=obj(00000000075167C0), L"r"=str(L"RegExp"), L"n"=obj(000000000B71C310)) context 0 line 0 char 2390 02b0:warn:jscript:print_backtrace 1 [unnamed](L"t"=obj(00000000075167C0), L"r"=str(L"RegExp"), L"n"=obj(000000000B7165E0), L"s"=obj(000000000B71C010)) context 0 line 0 char 21049 02b0:warn:jscript:print_backtrace 2 000000000B715440->[unnamed](L"t"=obj(000000000B7153E0), L"r"=obj(000000000B715440), L"n"=obj(000000000B4FDD90)) context 0 line 0 char 34610 02b0:warn:jscript:print_backtrace 3 [native code] 02b0:warn:jscript:print_backtrace 4 L"s"(L"t"=644.000000) context 0 line 0 char 548 02b0:warn:jscript:print_backtrace 5 000000000B51C790->[unnamed](L"A"=obj(000000000B51C730), L"a"=obj(000000000B51C790), L"i"=obj(000000000B4FDD90)) context 0 line 0 char 51886 02b0:warn:jscript:print_backtrace 6 [native code] 02b0:warn:jscript:print_backtrace 7 L"s"(L"t"=791.000000) context 0 line 0 char 548 02b0:warn:jscript:print_backtrace 8 L"n"() context 0 line 0 char 407 02b0:warn:jscript:print_backtrace 9 [unnamed](L"e"=obj(000000000B51C3D0)) context 0 line 0 char 2257 02b0:warn:jscript:print_backtrace 10 [unnamed]([detached frame]) context 0 line 0 char 0 02b0:warn:jscript:print_backtrace 11 [native code] 02b0:trace:jscript:set_error_location source L"return v(n),h(Z,e)?(n.enumerable?(h(t,L)&&t[L][e]&&(t[L][e]=!1),n=b(n,{enumerable:y(0,!1)})):(h(t,L)||q(t,L,y(1,{})),t[L][e]=!0),et(t,e,n)):q(t,e,n)},ut=function(t,r){v(t);var n=d(r),e=m(n).concat(ft(n));return W(e,(function(r){a&&!o(ct,n,r)||ot(t,r,n[r])})),t},ct=function(t){var r=g(t),n"... in L"(window.webpackJsonp=window.webpackJsonp||[]).push([[13],Array(176).concat([function(t,r,n){"use strict";var e=n(55),i=n(105),o=n(154),u=n(49),c=n(39).f,a=n(225),s=n(227),f=n(48),h=n(19),l=u.set,v=u.getterFor("Array Iterator");t.exports=a(Array,"Array",(function(t,r){l(this,{type:""... 02b0:trace:jscript:DispatchEx_Release (000000000B71C310) ref=1
Also, do you have the MutationObserver hide hack applied?
I didn't include that in my vanilla Wine patch set (see https://gitlab.winehq.org/achurch/wine/-/tree/ff14-launcher-9.x) but the launcher worked fine without it before the 6.58 update.
I'll see if that helps, and otherwise go bisect now that I have a working version to start from.