We have created our Azure devops Services extension and we make POST call through service connection which works fine if project is created by self. If it is shared with other team user, they do not have permission to make the service connection API call and hence our functionality fails to work as expected. Adding user to Project Administrator group also does not solve the issue.
You would keep getting error "You don't have enough permissions required for \"Post\" request." if checked in Developer tool when the drop down population fails. Neither any other project level settings could get the POST request working There seems to be some bug(https://developercommunity.visualstudio.com/t/cant-post-to-service-endpoint-from-a-widget/1111670) with Azure Devops platform where this issue is with POST type of API calls and not with GET requests.
The only permission group that solves this issue is ‘Project Collection Administrator’. But this is an organization level admin which should not be the case and Project admin should also be allowed to make service connection calls. Is there any other settings that can solve this issue.