Questie is unusable after login and start working only after I do some game action.
The problem is that at login _QUEST_LOG_UPDATE is happening before _PLAYER_LOGIN.
There's a variable intended for that in your code :

local hasFirstQLU = false

        -- manually fire QLU since enter has been delayed past the first QLU
        if hasFirstQLU then
            _QUEST_LOG_UPDATE()
        end

But it's always false, maybe something was lost in migration.
The problem is solved as soon as I set hasFirstQLU to true in _QUEST_LOG_UPDATE ().

Hey @sipertruk what version of Questie are you using? Since this topic comes up for the first time now it seems to be either a WIP state of Questie or a very rare scenario.

latest release 6.2.5
I must add that I didn't notice the problem until I clicked on a quest link that Questie uses to generate a tooltip, a short time after login.
Edit: Also I noticed before that map nodes would not load for a while after logging but didn't bother searching why because there was no error popping. And probably the quest tracker would not work but I use another addon for that.

Did you try to reset your saved variables? You will lose your Journey progress though (not the completed quests on the map etc) Check our wiki

I just tested dropping the setting files, did nothing to solve it.

@AeroScripts could know more about this, since he was the original author of the code piece.

Also @Logonz might have refactored this part as well, with the latest rewrite of the event initialization and handeling.

This is fixed in recent versions.