Class not found Exception for com.sun.webkit.MainThread with OSGI

A DESCRIPTION OF THE PROBLEM :
If you use an OSGI-environment and load a base 64 encoded picture in the WebView the jvm dies with a class not found exception for com.sun.webkit.MainThread. In an OSGI-environment the default classloader does not find the MainThread class, it could only be found by the bundle classloader.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Use WebView to load google.com in an OSGI-environment and search anything.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Application stays alive and shows the results.
ACTUAL -
The jvm dies.

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https://github.com/StegmannSystems/rcp.demo
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FREQUENCY : always