Has anyone noticed this?

[trandoductin]

in GIMP 2.10
When I write plug-in it runs multiple times fine
but if I add a
(PF_BRUSH, "brushname", "Brush:", 0),
as input
it only runs first time or I have to go to Filters/Reset All Filters to get plug-in input dialog to show up again.
Is that a bug? or is 0 in the line 
(PF_BRUSH, "brushname", "Brush:", 0),
causing this?
I tried (PF_BRUSH, "brushname", "Brush:", "Clipboard Image"), and that broke my plug-in altogether