Brave browser flags some tagged releases as pre-releases as marked on their releases page: https://github.com/brave/brave-browser/releases
Checking releases using the api confirms the latest release version is 1.86.148:
curl -Ls https://api.github.com/repos/brave/brave-browser/releases/latest | jq .tag_name -r
v1.86.148
However, https://release-monitoring.org/project/137663/ shows the current version as 1.89.21, which is marked as a pre-release version.
I confirmed that the brave is set to "Check releases instead of tags":
