Select all selects all unfiltered when I use filter

I use DataGridMultiseletion and have a list of for instance 200 rows. I use the filtering option and ends up with 12 rows. When I click on select all it selects 200 rows and not 12 as I would expect it to be. Is this a bug ?

You can adapt our demo to your needs. For example:

Thanks, that solved my problem.