React and Vue based spa Page Editor ITs fail very often with Timeout or StaleReferenceElement exceptions. Notably, the very same Angular tests seem to be doing just fine.

See PR builds where the problematic tests have been re-enabled, e.g. https://jenkins.magnolia-cms.com/blue/organizations/jenkins/platform%2Fce/detail/PR-578/9/artifacts 

A couple of recurring messages are logged in case of failing tests

info.magnolia.test.selenium.Selenium : warning: Failed to execute 'write' on 'Document': It isn't possible to write into a document from an asynchronously-loaded external script unless it is explicitly opened.

or, less frequently

ERROR info.magnolia.test.selenium.Selenium : Failed to load content \{ requestId: 442.152, url: http://172.17.0.1:4201/react-test?mgnlPreview=false&mgnlChannel=desktop, blocked reason: {}, resourceType: XHR, error: net::ERR_CONNECTION_RESET, cancelled: false \}
2022-06-22 07:15:34,149 INFO info.magnolia.test.selenium.Selenium : error: Failed to load resource: net::ERR_CONNECTION_RESET

Looking at failures recordings, no self-evident issue seems to occur, namely page seems to be rendered correctly and ready to be interact with.

Not sure what can be done on the PageEditor PO side, this appears to be beyond that. 

Foundation team will possibly try out Selenide, in hopes it helps in such a scenario. CC cmeier   

Solution

Eventually solved by MGNLTEST-267