If I pass --ie-compat to lessc using 3.10.3, I now get this error:

Unable to load plugin ie-compat please make sure that it is installed under or at the same level as less

As far as I can tell, you did not factor the IE Compatibility option out to a separate plugin (no reference in Changelog and I can't find any such plugin online). The --ie-compat option still appears when running lessc -h.

Please advise. Has this functionality been silently removed?