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Is there a limit to the number of selectors you can have in a CSS file for Mozilla Firefox to work?


I am writing the CSS code for my website and the CSS is being interpreted correctly by Chrome but is not even being read by Mozilla Firefox. When I use firebug, I can see that the classes appear in the HTML code but are not interpreted in the CSS.

The code for this page was recently added, which puts it on the bottom part of my CSS file. The CSS file has over 2.000 lines. Is it possible that Mozilla Firefox is limiting the number of lines it reads? If so, should I split the code in two or three CSS files (what is the limit per file)?

Thank you!

Additional System Details


  • User Agent: Mozilla/5.0 (X11; Linux i686) AppleWebKit/536.11 (KHTML, like Gecko) Ubuntu/12.04 Chromium/20.0.1132.47 Chrome/20.0.1132.47 Safari/536.11

More Information

  • Top 10 Contributor
2346 solutions 20793 answers

I don't think it's an issue of file length, however, as a test you could revert to your previously working file and place all the new CSS in a new file, and see whether that makes any difference.

If you clear the error console and reload the page, do you get any unexpected style warnings? By unexpected, I mean things other than, for example, -webkit-transform is not recognized and is being dropped. Illogical messages can indicate an unnoticed typo.

  • Top 10 Contributor
  • Moderator
10738 solutions 96600 answers

There is usually an error in the file (e.g. a missing quote) if Firefox doesn't read all rules.

The Error Console (Ctrl+Shift+J) or the Web Console (Ctrl+Shift+K) should show such an error, that possibly had a notification that Firefox reached end of file trying to recover.