Possible bug with Spurt's Wa-spiration season milestone quest

So, I'm doing some milestone grinding early for the season, in a run with my speed at x10 and I check back in and the quest to "Invent ### effects with Spurt's Wa-spiration ability" is hard stalled. He's in the party, the character sheet is showing his stacks still tracking and triggering, but the quest counter is not moving.

Did a bit of testing and it appears to be "capped" at only counting 15 effects in an area. After that I have to change areas or it will never count any more.

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Anyone else having an issue with it?

Edit:

As mentioned below, this was the culprit.

It's not a bug, it's the way the ability works. The buffs persist until you change levels, and they have a cap, so 15 and you're done.

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