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Firefox's fixed width screen font suddenly changes from default to a very hard-to-read script font. I must quit and reopen Firefox to revert to default. Can I fix this?

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When using Firefox 7.0 on my Mac (OS 10.6.8), suddenly the fixed width font, which I believe is Courier, is suddenly replaced by a nearly illegible script font. This seriously interferes with my work. When I quit out of Firefox and reopen it, the font reverts to default -- until the next time this suddenly occurs. Is there a fix?

When using Firefox 7.0 on my Mac (OS 10.6.8), suddenly the fixed width font, which I believe is Courier, is suddenly replaced by a nearly illegible script font. This seriously interferes with my work. When I quit out of Firefox and reopen it, the font reverts to default -- until the next time this suddenly occurs. Is there a fix?

All Replies (2)

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You can do a check for corrupted and duplicate fonts and other font issues:

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Thanks. I saw no evidence of a corrupted font, but there's a good idea here: simply change the default fixed-width font to another. That might resolve the problem.