I saw this last week, but I have not been able to find a solution in the coloring.
(Let me know if this is the same bug that was already discussed for the Unix Assembly)
Microchip's MIPS assembler allows usage of the '#' for preprocessing, but also for comments. I suspect this is confusing SE. Lines that do not have code, color as line comments, as is expected. But if such a comment follows code, it does not. I've retooled the previously submitted source/workspace to demonstrate.