Description:
Chat frame title and input area shows after completing a quest.

Steps to Reproduce:

• Step 1: Addon Options -> HUD -> Chat Frame Mouse-out Alpha to 0%
• Step 2: Complete a quest

Expected Result:
Chat frame stays invisible

Actual Result:
Chat frame Title and the input field are showing up until the next "hover" with the cursor. Then it fades out again.

Can confirm this.

This behavior also seem to affect the quest panel although I'm not sure if that's when completing a quest too, but the quest panel sometimes stays visible and needs to be hovered over again to reset the state, just like the chat panel.

Edit: After some mild testing, the questing panel bug comes from using the "Hide UI" feature of the DialogueUI addon where it hides the UI during a dialogue then unhides it when the dialogue window is left. The chat frame bug does still happen though.