fix(web-vitals): Add error handling for invalid object keys in WeakMap
#18809
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| // --- START Sentry-custom code (try/catch wrapping) --- | ||
| // Fix for cases where identityObj is not a valid key for WeakMap (sometimes a problem in Safari) | ||
| // Just return a new instance without caching it in instanceMap | ||
| return new ClassObj(); |
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Missing test for fix PR per review rules
Low Severity · Bugbot Rules
Per the review rules: "When reviewing a fix PR, check if the PR includes at least one unit, integration or e2e test that tests the regression this PR fixes." This fix PR adds error handling for invalid WeakMap keys in Safari but the diff contains no accompanying test to verify the fix works correctly. A test that simulates the Safari TypeError scenario would help prevent regressions.
JPeer264
approved these changes
Jan 14, 2026
| return instanceMap.get(identityObj)! as T; | ||
| } catch (e) { | ||
| // --- START Sentry-custom code (try/catch wrapping) --- | ||
| // Fix for cases where identityObj is not a valid key for WeakMap (sometimes a problem in Safari) |
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l: Is this issue easily reproducible? If so it'd be nice if we can somehow add a E2E test, if not I'm fine as is
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Lms24
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Jan 14, 2026
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Lms24
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Thanks for fixing! As discussed, it's not ideal that we can't repo this but I think in this case, let's merge and release it and check back with the affected customer if it fixes the issue.
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A customer experienced the following issue on iOS Safari 18.6.2:
TypeError: WeakMap keys must be objects or non-registered symbols.The culprit is probably in web vitals
initUniquefunction (which is vendored in).This fix adds a try/catch to handle edge cases where invalid keys are passed to WeakMap, returning a new instance without caching when validation fails.
Closes #18810 (added automatically)