After opening the Matlab Help Browser, Matlab might use 100% of one CPU core at about 25% duty cycle. Even after closing just the Help Browser while keeping Matlab itself open, this problem may persist.

Workaround: a one-time persistent setting. Type in Matlab:

com.mathworks.mlwidgets.html.HtmlComponentFactory.setDefaultType('HTMLRENDERER');

Restart Matlab, reopen and close Matlab Help Browser. The CPU is no longer hanging at 100% after closing the Help Browser. However, this simpler Help Browser is not as graphically nice as the default Java Help Browser. Clickable links won’t work in the help files.

Undo workaround: revert back to the default Java Help Browser with this one-time persistent setting. Type in Matlab:

com.mathworks.mlwidgets.html.HtmlComponentFactory.setDefaultType('HTMLPANEL');

then restart Matlab.