Fix DuckDuckGo HTML search
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#22090
- [x] There are tests for these changes
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Assign a name to iframes when loading the initial about:blank
Before, it would assign the name too late, causing scripts (which will not wait for another tick) to accidentally spawn pop-up windows instead of loading into the iframe.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#21886
- [x] There are tests for these changes
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Before, it would assign the name too late,
causing scripts (which will not wait for another tick)
to accidentally spawn pop-up windows instead of loading
into the iframe.
Null image source check for src, srcset and picture parent
<!-- Please describe your changes on the following line: -->
This PR includes a test which checks for empty src only.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#21221
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- [x] These changes require tests and added
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