How to solve "There is another glyph in the font with this unicode..." validation
FontForge 18:35 PDT
iMac Mini (Late 2014)
MacOS Sierra 10.12.2
I'm a relatively new FontForge user, this is my first font created with FF.
After creating a font in FontForge, removing all overlaps, adding extremas, correcting directions and auto-hinting all characters I try to generate a True Type font.
While generating it (incl. validation), FontForge detects a huge amount of "There is another glyph in the font with this unicode code point". No other issues.
Opening the respective characters I can't find anything wrong, I can't think of what to change. I tried Encoding > Detach and then remove all overlaps (mainly accent references) - that didn't help.
I don't understand what exactly these "There is another glyph..." error messages mean and how I can get these solved.
Does it have anything to do with my custom All European Latin character set (all accents and some ligatures)? If so should I just ignore these messages/issues?
Any help would be highly appreciated. Thank you!