I have worked with a few Malaysians....friends..P.R., one had even worked here for more than 30 years, hold a blue IC...retire back to Malaysia...revert back to Malaysian Citizen..use to drive a Malaysian Car to work..till it wasn't allowed..then bought a SINgapore car..commute daily between SINgapore & Johor...everyday..
this is just one case...many of the Malaysian friends I know of, who hold PR...and even took up the Blue IC...never renounced their citizenship...