Battery time remaining OS anomaly

Manjaro 21.1 Gnome 40 simultaneously reports Battery Remaining as 2hrs 39m & 1hr 16m.
Why the miss-match?

This pop up appears at 20% :

i have no idea, just pointing out that one says ‘remaining’ and the other ‘Approximately remaining’.
maybe different tools; one basing estimation on battery level and the other on current usage?