CI: Playwright shard a fails on every PR (items-planning-settings.spec.ts times out on #newEFormBtn) #2128

Problem

items-planning-playwright-test (a) is red on every recent PR (#2115, #2117, #2118, #2119, #2120, #2127), whatever the change. A permanently red shard hides real failures, and PRs get merged with a red check.

Failure

a/items-planning-settings.spec.ts:17 › "Application settings page - site header section › should go to plugin settings page":

Error: locator.waitFor: Target page, context or browser has been closed
  - waiting for locator('#newEFormBtn') to be visible

The wait for #newEFormBtn is unbounded, so the test sits there until the test timeout closes the page. The real cause (the start page never renders, a login/navigation or DB-configuration change in core, or a stale selector) is not yet identified.

Expected

Shard a is green on a PR that does not touch what it tests, and a failure names its cause within seconds (bounded waits).

Plan

• Find the root cause from the CI artifacts (trace, screenshot, error-context) and the shard's setup steps in .github/workflows/dotnet-core-pr.yml. Compare with the last green shard-a run.
• Fix the cause (spec, page object, or workflow step), not the symptom. No retries, no weakened assertions.
• Every wait in the touched code gets an explicit timeout.

🤖 Generated with Claude Code