Gboard beta v10.3 got a new setting where you can turn this feature off. Clipboard suggestions show copied text and images in the suggestions bar if enabled.
Tester Context:
- 📲 Gboard is an official keyboard app by Google that also comes as a default keyboard on stock Android devices.
- 📲 Gboard is also available in Beta and you can opt-in as a tester via Google Play.
Gboard - the Google Keyboard - Apps on Google Play
Gboard has everything you love about Google Keyboard—speed and reliability, Glide Typing, voice typing, and more Glide Typing — Type faster by sliding your finger from letter to letter Voice typing — Easily dictate text on the go Handwriting* — Write in cursive and printed letters Emoji Search* …
Source @9to5Google