This video is a must watch – #13 by danny – darktable

Yes, it seems to be harmless most of the time. Here’s some feedback from the author ot the video on that topic:

Right, so I have the “Highlight Reconstruction” module disabled, as I use highlight reconstruction in the “filmic rgb” module, when necessary.
That “Highlight Reconstruction” module is meant for when “filmic rgb” module is not enabled.
It’s better to use highlight reconstruction tab in “filmic rgb” module, when “filmic rgb” module is enabled.
It sounds convoluted, because it is…
To be honest, I was puzzled to why it’s ON by default in the latest Darktable, it shouldn’t be, IMO.