Issue when shrinking window and enlarging

I have the game client in window mode when playing and when I am going to afk and do something else on the pc I normally shrink the window down. Not minimize to tray but shrink it down to a small box.

I found that when I do this for some reason when i enlarge the window again fonts are all changed to a smaller size.
not the chat window, but quests, tooltips, and even the game menu you see when you hit escape.
Odd thing is when you run your mouse over the quest titles in the quests log they enlarge to normal size again.

Anyway, is there a fix for this?