Quote from AdirelleAs stated in the "Known issues and limitations" section of the addon page, this is a known "bug". It is actually not caused directly by Inline Aura but by some bug in Blizzard taint handling code. Inline Aura never calls :Show nor :Hide on the buttons.
By example, the error stack trace lists !BugGrabber as well as Inline Aura. Moreover, the error seems to come from Blizzard's function ActionButton_OnEvent, that neither addons call directly or indirectly.
It is quite possible that Inline Aura caused some taint but so far I could not find out how.
I'm sorry Adirelle, I must've completely missed that section. Sorry for bothering you.