Hello, I had the exact same problem and it drove me crazy for a while
What finally fixed it for me was going into Font Book on my Mac and checking for any duplicate or weird versions of Helvetica
I found some duplicates and disabled them
Then I ran sudo atsutil databases -remove in Terminal to clear the font cache and restarted my Mac
After that, fonts started showing normally in Opera again

Seems like it’s more of a macOS font issue than an Opera problem
Hope this helps you too

@vr51 i have the same issue with the last versione of Opera Mobile on Android.

I can't select the visual editor on WordPress, but only with "Desktop mode"

@newworldman I've always tested Vivaldi, but there always were some unexpected quirks. In my experience it doesn't run fine with WhatsApp in the panel, which works much more smooth in Opera.
Also, it happens to do not foreseen things in Instagram. Recently, I was logged out of my account, as I wanted to open my Threads account.
Otherwise a great browser, but it tends to make things to complicated in my opinion. And it's not willing to implement something like Aria, as they take a stand against AI.
For me it's Opera 1, Chrome 2, Safari 3 (on my Mac, but 2 on iPhone).

@kyu3 same problem here in using Chinese.
Please give it a fix.

Opera One(Version： 111.0.5151.0) (arm64)
Distribution Channel：developer
System：macOS ver. 14.4.1（build 23E224） 14.4.1 arm64
Chromium version：125.0.6382.3

@TheBooker66 Lol all we had to do was to wait for 2 years