As in my heavily modded game there are just 2 mods that have the following command
namely
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1967619462
and
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=1962650483
I post this in those two mods' discussion threads.

As soon as I try to edit a track which is on a bridge, by e.g. changing the track type or adding a signal, the game stucks and this is written to the log on each occasion:

The "stuckness" lasts for a couple of seconds, which is annoying when working on a track over a bridge.