* comments

Resolve "undulators: add 'undulator_prefix' in configuration"

Closes #1670

See merge request !3688

Ignore sphinx==4.0.0

See merge request !3691

Resolve "motion hook: post_scan, in case of dscan executed before motor has returned to start position"

Closes #2545

See merge request !3451

Resolve "Better Identification of communication errors on XIA startup"

Closes #2713

See merge request !3648

Fix blinking regulation plot legend

Closes #2743

See merge request !3684

Resolve "typos in undulators doc"

Closes #2747

See merge request !3687

Emit a PrepareScanEvent

See merge request !3655

- This makes the plot legend blinking

Merge branch '1773-scan-engine-doesn-t-call-all-stops-if-an-exception-occured-in-on-stop' into 'master'

Resolve "Scan engine doesn't call all stops if an exception occured in on stop."

Closes #1773

See merge request !2553

fix issue #1773: ensure reading task is killed when acq. stop fails, to allow cleanup of all devices involved in the scan

Before the fix, if a `acq_stop` was failing, `wait_all_devices` was stuck
thus preventing cleaning up of other devices.

Resolve "test_failure: test_multi_top_master"

Closes #2741

See merge request !3678

Merge black constaints in the main requirement

Closes #2723

See merge request !3680