This happens with the folders themselves. Sometimes I drag them into other folders accidentally. And I think it happens with standalone bookmark items in the toolbar too. 

I think it sometimes happens when I misclick one and try to drag to cancel it. 

Thanks for filing the issue!

From comment#0's statement "Maybe items could be "locked" or maybe make the drag action require a longer drag to be triggered." It is understood that this seems to be a Feature Request.

@Reporter: Could you please confirm on the same. Your confirmation helps us to triage this further in a better way.

Yes I can confirm.

Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

As per the confirmation by reporter, marking it as Feature and changing the status to Untriaged. Requesting someone from respective team to have a look into this for further inputs.

Thanks!