# Mastodon v4.6.6

- Product: Mastodon (https://whatsnew.fyi/product/mastodon)
- Vendor: Mastodon gGmbH
- Date: 2026-08-13
- Version: v4.6.6
- Original notes: https://github.com/mastodon/mastodon/releases/tag/v4.6.6
- Permalink: https://whatsnew.fyi/product/mastodon/releases/v4.6.6

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **changed** — Change mastodon:setup task warning about trademark to match masto but ignore subdomains
- **fixed** — Fix connection errors when processing fediverse:creator preventing creation of preview cards
- **fixed** — Fix Web UI being inaccessible with URLs ending with .zip
- **fixed** — Fix semitransparent background of picture-in-picture video player
- **fixed** — Fix title tooltip appearing for fullscreen videos
- **fixed** — Fix image preview too dark in alt text editor dialog
- **fixed** — Fix domain block impact queries being rejected
- **fixed** — Fix mobile navigation scrolling to top while opening
- **fixed** — Fix selected account being lost when creating a collection

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##### Upgrade overview

This release contains upgrade notes that deviate from the norm:

ℹ️ Requires assets recompilation

For more information, view the complete release notes and scroll down to the upgrade instructions section.

##### Changelog

###### Changed

- Change `mastodon:setup` task warning about trademark to match `masto` but ignore subdomains (#40143 by @ClearlyClaire)

###### Fixed

- Fix connection errors when processing `fediverse:creator` preventing creation of preview cards (#40135 by @ClearlyClaire)
- Fix Web UI being inaccessible with URLs ending with `.zip` (#40134 by @ClearlyClaire)
- Fix semitransparent background of picture-in-picture video player (#40132 by @diondiondion)
- Fix title tooltip appearing for fullscreen videos (#40127 by @diondiondion)
- Fix image preview too dark in alt text editor dialog (#40126 by @diondiondion)
- Fix domain block impact queries being rejected (#40122 by @ClearlyClaire)
- Fix mobile navigation scrolling to top while opening (#40042 by @sharlayan)
- Fix selected account being lost when creating a collection (#39897 and #40133 by @diondiondion and @sharlayan)

##### Upgrade notes

To get the code for v4.6.6, use `git fetch && git checkout v4.6.6`.

> [!NOTE]
> As always, make sure you have backups of the database before performing any upgrades. If you are using docker-compose, this is how a backup command might look: `docker exec mastodon_db_1 pg_dump -Fc -U postgres postgres > name_of_the_backup.dump`

###### Dependencies

External dependencies have not changed since v4.6.0.

- Ruby: 3.3 or newer
- PostgreSQL: 14 or newer
- Elasticsearch (recommended, for full-text search): 7.x (OpenSearch should also work)
- LibreTranslate (optional, for translations): 1.3.3 or newer
- Redis: 7.0 or newer
- Node: 22 or newer
- libvips: 8.13 or newer
- FFMpeg: 5.1 or newer

###### Update steps

The following instructions are for updating from 4.6.5.

If you are upgrading directly from an earlier release, please carefully read the upgrade notes for the skipped releases as well, as they often require extra steps such as database migrations. In particular, it is very important to read the [4.6.0 release notes](https://github.com/mastodon/mastodon/releases/tag/v4.6.0).

###### Non-Docker

1. Precompile the assets: `RAILS_ENV=production bundle exec rails assets:precompile`
2. Restart all Mastodon processes.

###### When using Docker

1. Restart all Mastodon processes.