[BUG]Waitforselector fail to read the element in execution but works when debugging.

[vrknetha]

Context:

• Playwright Version: [1.0.2]
• Operating System: [Windows]
• Node version: [12]
• Browser: [Chromium]
• Extra: [Jest]
  Code Snippet

Help us help you! Put down a short code snippet that illustrates your bug and
that we can run and debug locally. For example:

await page.waitForSelector('[data-target="#addRemoveModal"]');

Describe the bug

The selector works when I put on a breakpoint before executing this step but fails in execution.

<a _ngcontent-blu-c7="" class="btn btn-link" data-target="#addRemoveModal" data-toggle="modal" href="javascript:" xpath="1">Assign/Remove groups </a>

pw:api waiting for scheduled navigations to finish +1ms pw:api navigations have finished +3ms pw:api <= page.click succeeded +6ms pw:api => page.waitForSelector started +2ms pw:api waiting for selector "[data-target="#addRemoveModal"]" to be visible +1ms pw:api <= page.waitForSelector failed +30s

[pavelfeldman]

It could be that there is this button on a page, but it is invisible. Then another button matching the same query appears, but we are still waiting on the old one. When you set a breakpoint, you give this old button a chance to disappear, so we never see it / are mislead with it when we wait. Does that sound plausible?

[pavelfeldman]

Assuming the suggestion above was the case.