I do not see a known issue of this sort - https://www.tableau.com/support/known-issues
If the issue persists, please consider opening a ticket with Tableau Support to allow for tracking of the issue with the support team and verification that no other cause exists.
Sorry haven't updated this with holidays and all. The Tableau Support Rep verified this issue exists in 2018.2.x and supposedly the fix went into 2019.1. Not sure why it isn't in the formal list on their site that you reviewed.
Below is the response from the Support Rep from last week:
It looks like the fix went into 2019.1 versions, but wasn't considered for backporting to 2018.2.x. I just did an install of 2018.2.5 just to verify and the extra folder does indeed still appear in that version.
Kevin - thank you for sharing your findings with the community!