In Rust there is a so called turbofish operator which is used by generic function calls which makes use of the character sequence ::<. Unfortunately FiraCode causes this sequence to look a bit weird due to the font ligatures moving the middle colon up a bit:

I imagine this is due to the fact that :< is considered a ligature in the other category, but I wonder if it would be possible to have this behaviour reset for the ::< character case given that the two colons are just scoping operators here, assuming this is possible.