this post was submitted on 13 Jun 2026
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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. ๐Ÿค”

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. :)

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I think the content might matter here. This could be intentional design against people just copy pasting all the training material out, or against AI scraping.

Some sites disable copy and paste, but that can be bypassed client-side. More complicated manipulation of the content so it's usable visually to human readers but not parse-able programmatically would sidestep that. Now someone wanting to steal the data would need to screenshot it all and feed it through OCR software.