Hi, I came across a funny web browser rendering(?) issue.

There is a webpage (it's a certification exam preparation training site, but the content doesn't matter here). I have text on the screen, and when I mark it, some (formerly invisible) overlay text emerges and gets actually marked, instead of the text I see on the screen. The marked text seem to have a different font.

But what confuses me most about it, is that the original and the marked text are actually notably DIFFERENT STRINGS. 🤔

Note the words
"defines"- where the "f" seems to be a special character, that @Vivaldi renders as a box, @firefox doesn't render it at all.

"partner" - where there seems to be typo in the copy-text ("parner"), but not in the visible text.

To me that's a hint, that this isn't a rendering glitch, but something that was designed like this on purpose.

Can anyone explain to me what this is and/or what the intention behind it may be? I'm really curious...

First screenshot is the text is just the website as it appears to the plain eye.
Second is a screenshot when text is marked in Vivaldi (Chromium engine) and the third is the same in Firefox

#fediknowledge #WebDesign
boosts for reach appreciated to solve the riddle. :)