## Bug fixes

- `adjacent_vertices()` and `incident_edges()` are now correct if the `"return.vs.es"` option is `FALSE` (@stibu81, #1605, #1606).

- Fix protection errors reported by rchk (#1592).

## Continuous integration

- Change `Makevars` only after installation of R.

- Use GLPK on macOS.

- Add required rgl version (#1584).

- Install GLPK on macOS.

- Bring back extra workflow.

- Import from actions-sync, check carefully (#1600).

- Remove covr, handled elsewhere.

- Fix extra workflow.

- Remove noise.

- Sync workflows (#1589).

## Documentation

- Tweak NEWS \[ci skip\].