Crash of tests including writing (search, login, add an event...) with Selenium IDE in Firefox

[agilare]

A lot of tests in tests/ladecadanse.side crash in Selenium IDE with Firefox with this error : .createEvent(...).initKeyEvent is not a function
This problem has been noted here SeleniumHQ/selenium#16915

These tests still seem to be working in Selenium IDE for Chrome (but : SeleniumHQ/selenium-ide#1900) and Edge