>>12835741Depends on the software. If it's written by some academic funded by grants and publishing open access & open source then email them and let them know, they'll probably be grateful and you can get your good deed for the day done, depending on the size of the bug and your rewrite you might even get developer credit.
If it's some private company milking department budgets with closed source stufff: 1. why are you even using it? 2. Submit a bug if it breaks functionality and you can't fix it without decompiling their bullshit. Offer paid consultancy service if they want you to help fix it.