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I don't know how to reduce the file size. Please let me know if there is anything I need to do 🙏

Also, no need to worry about the ci/circleci; Filesize check when it's a close call like this. We'll adjust it later.

One more request, if you have time: if you can add a regression test (in this module) that fails without these changes, that will help us make sure we don't regress this behavior (without realizing it) in the future.

@benjamn

if you can add a regression test (in this module) that fails without these changes, that will help us make sure we don't regress this behavior (without realizing it) in the future.

I agree. I think the following test should be added:
kazekyo@8569139#diff-7bca58c8d152cf9947df8bd35ec7ae4286339c99d95afb9437447128f7724791R529-R531

But I have two problems 😅

First, I upgraded React version to 18, but in this test, the component is not remounted even if StrictMode is enabled. So the test is always PASS. I do not know what reason this is occurring.
Do you know of a way around this problem?

Second, this test requires React v18. I do not know of any way to reproduce this situation other than using React v18 StrictMode.
I confirmed that some unrelated tests failed due to the effect of upgrading React to 18.

Test Suites: 10 failed, 106 passed, 116 total
Tests:       20 failed, 15 skipped, 1740 passed, 1775 total
Snapshots:   135 passed, 135 total
Time:        33.893 s, estimated 39 s
Ran all test suites.

Should we fix all the failed tests with this PR?

It sounds like we need to start a React 18-only test suite, to accompany our existing React ≤17-compatible test suite. I can work on that today!

We will find a way to properly test this code in multiple major versions of React, but that does not need to block shipping these changes. Thanks for your thoughtful analysis and for coming up with this solution @kazekyo!

I think apollo-client has an issue when re-mounting subscription components without the StrictMode now.

This issue is reproducible on our open source desktop app ExpressLRS Configurator. We were able to fix subscription re-mount issues in development build by wrapping whole app inside <React.StrictMode> component. See ExpressLRS/ExpressLRS-Configurator#351. But nightly builds are still not working at https://github.com/ExpressLRS/ExpressLRS-Configurator-Nightlies.