Personal fork of HeliBoard that strips the system spell-check suggestions popup so it only offers “Add to dictionary” / “Delete” instead of a long list of correction candidates.
Source: github.com/d33mobile/HeliBoard (branch: nopopup)
Use this combined URL in F-Droid — it includes the SHA-256 fingerprint of the repo signing key so the client can verify subsequent updates:
https://d33mobile.github.io/heliboard-nopopup-fdroid/repo?fingerprint=525e516e3ae7763a588950e9692161029de2e373a9151455ff6f9c17179d15a7
Or use the bare URL (less secure: skips fingerprint verification on first add):
https://d33mobile.github.io/heliboard-nopopup-fdroid/repo
applicationId is helium314.keyboard.nopopup,
so it installs alongside upstream HeliBoard rather than replacing it.