This is the follow up ticket for MGNLPN-131 which disabled variant resolution in pages app, but resolution of variants in VariantResolverFilter in case of preview app is still not skipped.

Problem

There might be situations where variant resolving might be triggered when in AdminMode (in the PageEditor or in PreviewApp without explicitly setting preview parameters). For example:

• mainNode
  • variant-0 (trait: date=today)
  • variant-1 (trait: userAgent=Firefox) (using Firefox for preview)

• In PreviewApp we want to maintain variant resolution! But we don't to resolve a variation without specified parameters (e.g. opening the preview app)

How to reproduce on localhost

"Attach" a date trait with the date set the "today" (See above example).

Suggested solution

https://developer.mozilla.org/en-US/docs/Web/HTTP/X-Frame-Options (this can't be used as this header is not set)

We should use the GET parameter mgnlVariant to identify a needed bypass of the filter as this parameter is not used in the PreviewApp.