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## Summary
<!-- Provide a brief summary of the changes you have made and most
importantly what they aim to achieve -->
Remove the portWithFallback helper and update port comparisons to use
URL.port directly. baseIsEqual now compares ports via url.port (no
80/443 fallback), and SafeScriptMessageHandler passes url.port ?? 0 when
building origin keys (security origin uses port 0 when unspecified).
This simplifies port handling and avoids implicit defaulting to standard
ports.
## Screenshots
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screenshots in light and dark mode. -->
## Link to pull request in Documentation repository
<!-- Pull requests that add, change or remove functionality must have a
corresponding pull request in the Companion App Documentation repository
(https://github.com/home-assistant/companion.home-assistant). Please add
the number of this pull request after the "#" -->
Documentation: home-assistant/companion.home-assistant#
## Any other notes
<!-- If there is any other information of note, like if this Pull
Request is part of a bigger change, please include it here. -->
<!-- Thank you for submitting a Pull Request and helping to improve Home
Assistant. Please complete the following sections to help the processing
and review of your changes. Please do not delete anything from this
template. -->
## Summary
<!-- Provide a brief summary of the changes you have made and most
importantly what they aim to achieve -->
## Screenshots
<!-- If this is a user-facing change not in the frontend, please include
screenshots in light and dark mode. -->
## Link to pull request in Documentation repository
<!-- Pull requests that add, change or remove functionality must have a
corresponding pull request in the Companion App Documentation repository
(https://github.com/home-assistant/companion.home-assistant). Please add
the number of this pull request after the "#" -->
Documentation: home-assistant/companion.home-assistant#
## Any other notes
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Request is part of a bigger change, please include it here. -->
