This morning I've installed the newest version of PixInsight which has very interesting new features for Image Synchronization to compare one or more pictures in detail and MultiscaleGradientCorrection with the new MARS Database.
All that this tab does is launches a web browser from within PixInsight (internally) and then goes to a web address. I do not know why the internal browser is not working for you. However you can still post questions on the PixInsight forum and everything. Just use a web browser outside of PixInsight.
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