After creating, en cleaning up device groups i saw the counter only increase and after removing the group not decrease in numbers.

Ha yes, this is because when you delete a device group, it just marks it as deleted so I can "un-delete" it if an agent connects back to a deleted device group. I will fix this now to only count active device groups.
Just published MeshCentral v0.5.35 with a fix for this!
Your fast, confirmed fix
Thx again
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Just published MeshCentral v0.5.35 with a fix for this!