Do we need to replace unsuported lines before processing?

[jakkubu]

In these lines we are replacing unsupported ANSI codes: https://github.com/aziz/SublimeANSI/blob/3e49dc6531177e0fcdf27c9e5dd225d8d86865ed/ansi.py#L149-L153

Is is necessary? We remove them later, during looking for ANSI colour codes this replacement shouldn't change much. Am I missing something?