I have experienced something similar when inviting to Secret groups. Are you sure it is the browser?
In my case it was the fact they had not registered so they did not have a community account. The way I resolved it was to send a welcoming invite asking them to log into the community then message me; once I received the email, I invited them from within the Secret Group and they never had errors.
Hope that helps.
We have never had to make our user register for a community account before. I will try this and see if it fixes the issue.