When Roblox asks for a keyboard (showKeyboard), a world-locked panel
opens below eye level as an OpenXR quad layer. Controllers point at keys
and the trigger types; text and key presses go through the same platform
events as the desktop keyboard, so the focused TextBox edits identically.
The layout is US QWERTY without the function row or Ctrl/Alt, with one-shot
Shift, Caps Lock, Tab, Backspace auto-repeat, Enter and Close. A trigger
aimed at the panel is withheld from Roblox so a key press is not also a
click. A text field above the keys mirrors the focused TextBox, whose
desktop overlay never reaches the eye images. MOCKTAIL_VR_KEYBOARD=0 turns
it off.
dim-ghub