ID made with Kershaw & Allen 2020 and this paper which has a detailed plant description on page 3:
http://www.phytoneuron.net/2018Phytoneuron/02PhytoN-Potentillarubricaulis.pdf
Better leaf photos are here:
https://inaturalist.ca/observations/180696705
I only noticed plants with 3 leaflets, but didn't examine too many.
Will have to revisit next July.
Sample collected by permit.
Found next to old beaver pond in open disturbed area
Capsules are 2.3-2.6 mm long
Seeds are 0.4-0.5 mm long
Auricle is leathery and short