Francis @ Agileware

@AbhijitNage123 does your fix address ServerSideRender previews in the general case? As I have exactly the same problem with Pods block previews and a custom dynamic block that uses ServerSideRender...

@KarinG the same change applies to the to the 8.x-5.x branch without issue, so see #410 As noted there though, I don't actually have a D8 CiviCRM system to test...