OnePlus
Enable or Disable Long Press for Symbols on the Keyboard auf OnePlus
On many OnePlus keyboards, letter keys show only the main character until you switch to the symbols layout with the 123 key. Enabling long press for symbols adds a small secondary character to each key, so you can insert it by holding the key instead of switching layouts.
This option lives inside the Gboard keyboard preferences, not in the general OxygenOS display settings, which is why it can be hard to find. If the toggle appears missing, confirm that Gboard is set as your active virtual keyboard.
To enable or disable it: Settings ➔ System ➔ Languages & input ➔ Virtual keyboard ➔ Gboard ➔ Preferences ➔ enable or disable Long press for symbols.
Turning the setting off removes the small symbol previews and returns typing to a clean, letter-only key layout. Turning it on can slow down typing slightly at first, since each key press now requires a moment to decide between a tap and a hold.