What permissions do I need in source and target to run the Azure DevOps Migration Tools?
I've tried to find the information here and in the docs without success.
Edit: I found something about adding my account to the Project Collection Service Accounts group which is basically same as Collection Admin. But docs also says this is not needed for "VSTS" (Azure DevOps Services). So still dont know what is needed when targeting Azure DevOps Services...
It really depends on how you have your Azure DevOps Migration Tools run configured.
The account that you run the migration under will need to have permission to everything that you're accessing.
For example, if you are just running the WorkItemMigrationConfig and migrating work items only (not Area Paths, Iterations, or Tests), you could get away with only having contribute permissions within the destination project and reader permissions within the source.
However, I'd recommend making sure that the account you're using has at least Project Administrator rights within both the source and destination repositories to avoid any issues.