CK4.02 and 4.2, inline mode, Firefox, Image property dialogs (and possibly others)
I find that on setting syle data on the Advanced tab, this info often gets silently deleted when you OK the dialog. This is particularly aggravating as you don't know it's happened, and thus have to keep checking and rechecking the image properties to see what's been lost this time.
Some info seems to survive, eg width and height, but other items do not, even though they are syntactically valid. There have been posts about similar issues as far back as 2010, but seemingly no answer found.
I could hazard a guess that there is some kind of syntax-checking 'wizard' kicking-in here.. and like spell chequers these things of coarse always know butter than the user.
Probably ACF, which was
Probably ACF, which was implemented in 4.1, but you say this is happening in CKEditor 4.0.2? In any case, try adding this code to your config.js file and see if it fixes it for 4.2:
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