This sounds like a browser scaling issue to me. Maybe related to the font scaling in linux. My thought is that if you have a wider font than typically used for a primary broswer text font, ...
My "browser font" is whatever I say it is.
Is a "10 point" font really 10 points? Nope. Every system I've seen says "10 points == so many scan lines". How many?
In print, it's 72 lines per inch, at about 300-1000 lines per inch of resolution, depending on the quality of the printshop. Or, about 72-150 lines of resolution for self printing (oddly, with up to 1440 lines of resolution for positioning, but you can't print a checkerboard anywhere near that level of detail).
On screen? Very often it's spec'd at 92 dots per inch, using monitors that can't resolve better than 72. There's a push to use "higher resolution", that doesn't turn into "Same size letter made sharper", but instead "same bad resolution made smaller".
The only solution to that is to make things bigger to compensate for the smaller dotsize. Use more dots.
HTML stinks for that. CSS specifies things in terms of pixels. Etc.
Browser scaling doesn't work properly. You can't say "Treat my window as 800 virtual pixels wide, and scale the display onto that". That would be nice for almost everything. But no -- depending on the browser, you might get "Alright, we'll scale your screen, but now you have to move left/right on every page", or "We'll scale up text, but keep graphics at exact pixel size", or "We'll scale things nicely -- mostly -- but any text displayed relative to the bottom or the right will be misplaced", or ...
And I've seen where some websites use CSS in a way that it works fine with one scaling, while another website uses CSS in a different way and it doesn't work with the same scaling. But change browsers, and ...
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The bottom line: You don't know my screen size. You don't know my dot pitch. You don't know my eyesight. You don't know what size I have to use to make a readable screen. Stop assuming that my system is a match for yours; stop assuming that my eyesight is a 20-year-old's. Stop assuming that I like 2 80-character-wide (plus scroll bars) xterm windows on-screen at once.
If your website does not work with ANY browser text size --
If your website does not work with Lynx --
If your website does not work without CSS working the way you want it to work (worst is assuming IE's CSS bugs) --
Then your website is broken.
CSS should be display HINTS, not absolute requirements.
