There is a new Power BI admin setting - "User experience experiments", which is enabled by default.
When this is enabled users in the same tenant may find their "Shared with me" folder in another location, under "Browse" or lose their "Favourites" shortcut etc. This is not changed across the entire tenant, but it appears a random number of users get a random number of these changes.
I understand the need for Microsoft to experiment with these type of changes, but please can the default for this switch be "Disabled" as it is very confusing for users who meet this UI change, when their colleagues do not. It is resulting in an increasing number of support calls as users don't know why their screen is different from their neighbours. It would be far better for users to knowingly opt in to these changes, rather than get confused by a randomly changing user interface.