Bug report (I think):
I’m using the key command option-command-8 for a body style. When I type the command, it toggles the font size between 13 and 14. It should just stay at one size.
There is no body style defined in Scrivener, so presumably this is something you defined yourself - in which case I recommend checking the style and whether it’s set to affect font size.
Also, I strongly recommend against using a body style in your text. Scrivener doesn’t define a “Body” or “Normal” style for a reason - it’s better to use “No Style” for most text and only use styles for text that is different. Otherwise you may not get the results you hope for when compiling.
All the best,
Keith