I used Fontforge to add accents to letters which didn't have any (in a handwriting font called "Austin"). As I'm writing in French I need é, è, etc.
I opened the Austin.ttf file, copy-pasted 'e' into the slot for 'é' and added an accent. And so on for the other letters I needed. Then I saved and generated the font.
My modifications have been saved. If I re-open the Austin.ttf file, I see them. But nothing else sees them.
I load Austin.ttf into an html file. It displays the Austin font, as it did before, except for the accented letters. These appear in another, more standard, font.
I copied back my new Austin.ttf in /usr/share/fonts/TrueType and tried other programs (KolourPaint and Open Office). é and è still appear in another font.
I tried re-encoding as Latin1 (iso 8859-1). No change.
I modified 'f', giving it a longer downwards tail. I did this because it was an existing letter, displayed in Austin font.
Saved and generated again.
My modification is ignored!
But when I reopen Austin.ttf with Fontforge, I can see it!
It's as if the computer "remembered" the original version of Austin.ttf and refused my modifications. But where could it remember it, given the only place where the Austin.ttf file was saved was in /usr/share/fonts/TrueType ???