develop
Convert more cached return values to immutable types (#16356)
Remove redundant "coding: utf-8" lines (#9786)
Fix typechecking with twisted trunk (#16121)
Add missing types to tests.util. (#14597)
Use full GitHub links instead of bare issue numbers. (#16637)
Speed up persisting large number of outliers (#16649)
Fix edge case where a `Linearizer` could get stuck (#12358)
Support RFC7636 PKCE in the OAuth 2.0 flow. (#14750)
Remove unnecessary reactor reference from `_PerHostRatelimiter` (#14842)
Fix a bug where servers could be marked as up when they were failing (#16506)
Check the stream position before checking if the cache is empty. (#14639)
Task scheduler: add replication notify for new task to launch ASAP (#16184)