(Revised at 6:39 p.m. MDT July 13, 2020.)

A video shot from a helicopter on July 9, 2020 got good footage of two firefighters rappelling from a helicopter to initial attack the East Plum Fire about seven miles southwest of Larkspur, Colorado, south of Denver on the Pike & San Isabel National Forests.
It appeared to be routine at first. One of them landed safely on the ground, but the other appeared to have difficulty descending through a tree. Either the firefighter or the person’s rope, or both, apparently became entangled in the limbs of a fairly small tree about 15 feet off the ground. While the firefighter on the ground looked up and moved around, the hung-up firefighter was actively moving his or her arms around, perhaps trying to gather the rope below so it could be untangled and dropped again, so the rappel could be completed.

This went for about two and a half minutes before the firefighter made it to the ground, and all the while the helicopter was hovering. The view from the news helicopter’s camera was partially blocked at times, so I could not determine if the helicopter was maintaining tension on the rope, or if the weight of the firefighter was supported by the tree. But I imagine the pilot had to be very careful to not drag the firefighter up through the tree’s canopy. The rope and the firefighter possibly being entangled in the limbs could have made that inadvisable.

A total of six firefighters rappelled into the fire which ultimately burned 0.3 acre. The next day, July 10, a hotshot crew hiked in, built and improved fireline around the fire, then hiked out. Six firefighters, possibly the six rappellers, spent two nights on the third of an acre fire and hiked out on July 11.
An air tanker dropped retardant on July 9 and a heavy helicopter assisted firefighters by dropping water on July 10.
The video can be seen on Facebook. The rappel begins at about 7:20.
More details about the East Plum Fire from the U.S. Forest Service.
We reached out to the Forest Service for more information, and received this from Lawrence Lujan, Regional Public Information Officer:
Rappelling into trees is common in steep, rugged and heavily wooded areas. Firefighters train regularly to handle such occurrences. The Forest Service firefighter from Montana touched down safely with no injuries.
(Revised to add a quote from the US Forest Service received after initial publication)