Old VST not redrawing with VST3_SDK

first, thanks for this amazing library!
second, it may not be related entirely to juce code, but may be somebody here have a work around, or can point a direction toward resolution.

problem :
in a plugin host (demo plugin host for example) compiled on juce 5 and VST3_sdk 3.6.7 on osx
on some “old vsts2” : when changing a param inside vst pluginwindow, the pluginwindow is not redrawn accordingly until moving the pluginwindow on screen.
not working vst2 examples:

I remember that some older version of juce/VST_SDK did not have this problem, but I can’t find the last working combo

again, I understand these plugin are old and maybe badly implemented, but let’s put that on JUCE completeness sake…