Free / open source code can be _forked_ by anyone, but in doing so one often takes on a maintenance burden bigger than one's current codebase.
To have a fix accepted on an OSS project means fixing it not just for your use case but also for every other user of the project, on every target platform, while aligning with the goals of that project. If you can get anyone to look at the PR in the first place. Assuming you've used the framework to save time, you probably don't have time to go through all that and your deadline will not wait a month or six for your code to make it into a release. Depending on your employer you may well need internal permission and legal sign-off to contribute to an OSS project in company time which is yet another hoop to jump through; though that goes for forking too.
To have a fix accepted on an OSS project means fixing it not just for your use case but also for every other user of the project, on every target platform, while aligning with the goals of that project. If you can get anyone to look at the PR in the first place. Assuming you've used the framework to save time, you probably don't have time to go through all that and your deadline will not wait a month or six for your code to make it into a release. Depending on your employer you may well need internal permission and legal sign-off to contribute to an OSS project in company time which is yet another hoop to jump through; though that goes for forking too.