Well there are 2 ways to deal with this as far as
I know:

"I am a developer of the project and I just want to
add my work in an organized manner"
A new branch is created on the LOV2 repo. One
and only one issue is fixed on the branch, and then
a merge request is created. If a solution for another
issue is found, another branch is created and a new
pull request is also made, and so on and so forth.

"I am not a developer of the project, but I would like
to contribute with fixes"
A fork of the project is made. The master of the fork
should be kept up to date with the master of the
original repo and issues are fixed in a new branch of
the fork (just like you would on the original repo). Then,
it should be possible for a cross-repos merge request to
be made between branches. Something along the lines
of "I have this issue fixed on my fork in branch 5. I want
to merge this specific branch to the master of the original
repo. Can you guys approve my request?"

Now it is your choice on which category you fall into.

Stefan