Probably all tags except highway=street_lamp and bin=yes. They seem to be copy-pasted from a specific node. I'm not sure about all nodes, but I've checked a few nodes and it seems it's like this for all nodes modified.

The added tags include traffic_sign=* tags for a direction sign to Kallahdenniemi and a cycle-footway sign. This was one thing which raised suspicion as there are no signs like these at a park near me where the edits have been made, as the location on the direction sign is in a very different place. I started to wonder, "why there is signs like this?" :D

And there is an power=* tag which seem to be usually used as main tags on nodes. There's no information about using them in combination with tag highway=street_lamp in the wiki.

Hello,
it's great that you are fixing tagging issues.
But there's one thing with the edits. There's some tags added to the edited nodes (which are all the same) which seem to not be verified on the ground.
It would be nice if the changes are reviewed (and reverted when necessary).

The data was added from the following removed ways:
osm.org/way/1104523679
osm.org/way/1104523676
osm.org/way/1104523677

Sourced from local knowledge