It's nonsensical to apply power levels to guest users.

Refiled from https://github.com/vector-im/element-web/issues/2550.

We don't have any good way to identify guests though (short of numeric IDs?!) to apply this though.

Start with the refiled Element Web issue at https://github.com/vector-im/element-web/issues/2550 and review how the Matrix specification currently describes power levels for guest users. Clarify how guests should be identified and whether power levels should apply to them; done requires an agreed specification change, since this issue does not name files or tests.

Written by the indexing model from the issue text.