odrive has a trash that is used to guard against accidental deletes. Since getting and keeping your data in the cloud service you have chosen to link to is our highest priority, we want to make sure nothing is accidentally removed from there.
You can read more about Trash and the notifications (including how to disable them) here:
If there is activity within odrive (you are syncing content) then you could see some icon flickering, especially if you are looking at the left-side pane where the folder tree view is accessible. Is that where you are seeing the flicker?
Here is a thread that goes through some behavior that sounds similar to your own:
This may be related to question #2 above. CPU will naturally be elevated if there is sync activity happening (active uploading or downloading), but it can be amplified by the left Explorer pane effect mentioned in #2.