Many feature requests and issues exist for multiple user support. Some of the most relevant issues in the original Trilium repo are:
(#3546, #1375, #2679, #2143, #2109, #1527, #1436, #964, #600, #450, #169)

Instead of migrating each of the issues, we will link to them here, and if desired, Zadam can close the issues on his repo and link to this issue.