Better fix for question mark boxes in Firefox ?
This fixed my problem with question mark boxes (which I have seen, then not seen, then seen again over versions of FF on a Mac): https://support.mozilla.org/en-US/questions/1178462
But the answer is 3 years old and nearly 30 FF versions ago, and furthermore requires lowering security. Is there a newer, better solution for fixing the problem with seeing question mark boxes instead of glyphs for certain fonts? (And one that doesn't require me to constantly toggle "Allow pages to choose their own fonts, instead of your selections above" in Preferences, which only works sometimes anyway.)
Hi Tim, "Allow pages to choose their own fonts" is necessary for webfonts (also known as remote fonts or downloadable fonts). You are correct that this is not always the problem.
Adjusting the sandbox was a workaround for users with third party font managers that stored fonts in locations on disk that Firefox's sandbox didn't allow access to. To get more locations added, or to get advice on how to potentially get the fonts into an allowed location, I suggest filing a new bug and having a discussion with the developers about where your font manager stores its fonts.
If you are not using a third party font manager -- just the built-in stuff -- then it could be a problem with a specific font. Do you know which one Firefox wants to use and is using instead? You can use the Fonts panel of the Page Inspector tool to find out. Right-click (one button? Ctrl+Click) the row of little boxes and choose Inspect Element. Firefox should open the Page Inspector tool with that element of the HTML selected. On the right side, where you see panels with Layout, Computed, and so forth, find Fonts and click the tiny triangle at the end of that row to show Fonts. (I have attached an old example of this for reference.)