## Summary
- Fixes bug where `fetch()` with mTLS would use the first client
certificate for all subsequent requests to the same host, ignoring
per-request `tls` options
- Corrects `SSLConfig.isSame()` to properly compare all fields (was
incorrectly returning early when both optional fields were null)
- Sets `disable_keepalive=true` when reusing cached SSL contexts to
prevent socket pooling issues
Fixes#26125
## Test plan
- [x] Added regression test `test/regression/issue/26125.test.ts`
- [x] Verified test fails with system Bun 1.3.6 (demonstrates the bug)
- [x] Verified test passes with patched build
🤖 Generated with [Claude Code](https://claude.ai/code)
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Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
