You're on Mac, I guess? Did you try:
1. Turn on "Application Frame" under menu "Window".
and / or
2. Navigate to Preference -> Advance Type -> Type Contextual controls and uncheck it.
just tested the Color Panel with selected text where the OpenType Adornment was visible with the selected text. Application Frame was off.
InDesign CC 2017 v18.104.22.168
And yes, I can see that bug where the editing field of a panel lost focus and the values are replacing selected text.
Now we have three cases where the bug hits: The Paragraph Panel, the Control Panel and the Color Panel.
Every time the solution was to use the Application Frame and/or to shut off the OpenType Adornment features.