Bump version to 3.5.3 (Gargron)
https://github.com/mastodon/mastodon/pull/18530

Fix errors when rendering RSS feeds (Gargron)
https://github.com/mastodon/mastodon/pull/18531

Fix concurrent unfollowing decrementing follower count more than once (Gargron)
https://github.com/mastodon/mastodon/pull/18527

Fix being able to appeal a strike unlimited times (Gargron)
https://github.com/mastodon/mastodon/pull/18529

Fix being able to report otherwise inaccessible statuses (Gargron)
https://github.com/mastodon/mastodon/pull/18528

Fix empty votes arbitrarily increasing voters count in polls (Gargron)
https://github.com/mastodon/mastodon/pull/18526

Fix moderator identity leak when approving appeal of sensitive marked statuses (Gargron)
https://github.com/mastodon/mastodon/pull/18525

Fix suspended users being able to access APIs that don't require a user (Gargron)
https://github.com/mastodon/mastodon/pull/18524

Fix confirmation redirect to app without `Location` header (Gargron)
https://github.com/mastodon/mastodon/pull/18523

Fix follower and other counters being able to go negative (Gargron)
https://github.com/mastodon/mastodon/pull/18517

Add ES6 compatibility to browserslist (ykzts)
https://github.com/mastodon/mastodon/pull/18519

Remove 3.3.x from supported versions in security policy (Gargron)
https://github.com/mastodon/mastodon/pull/18516

Fix regression in `tootctl search deploy` caused by unloaded attribute (Gargron)
https://github.com/mastodon/mastodon/pull/18514

Change "dangerous" to "sensitive" in privacy policy and web UI (Gargron)
https://github.com/mastodon/mastodon/pull/18515