Yeah that too. I have been avoiding Ethereal missions
I bet he meant that certain localized strings would bust out of the icon, due to their length. I, however would suggest simply allowing to override the default icon wholesale.
Pretty much like we have a custom image for TFTD buttons (
data\Resources\UI\reserve.png), we could also have a well known location for localized icons such as
data\Resources\UI\Localized\ .
Translators could draw localized versions for these buttons and drop them into that folder, named like
launch.pl-PL.png and the game could try to load the one that corresponds to the current locale. If no localized version was found, the game would simply fall back to the default graphic in the original game data.