Hi Hiroyuki!
It is possible the issue is caused by the html renderer used by MATLAB to view the Help browser. You can use the following commands to try changing the Help browser renderer (available options depend on your system):
webutils.htmlrenderer('basic');
webutils.htmlrenderer('chromium');
webutils.htmlrenderer('mozilla'); % Only on MAC or 32-bit Windows
webutils.htmlrenderer('ie'); % Only on 64-bit Windows
webutils.htmlrenderer('safari'); % Only on MAC
To restore to MATLAB's default renderer, use:
webutils.htmlrenderer('default');
You can also always access the documentation on the web: https://www.mathworks.com/help/matlab/index.html
Hope this helps!
Kris
