Mattermost

The server fails to start after the upgrade because a migration cannot convert a column to JSONB, leaving the instance down.

Affects: Debian self-hosters

Every day or two, users in an organization stop receiving direct messages in the desktop app until it is quit and reopened.

Affects: organization using the desktop app

A paying customer saw the price double for features they did not use, then double again, ending up quoted more than an O365 account for the same features. This soured them on the open core model.

Affects: paying enterprise customer

A work user rates Mattermost as good as Slack overall but calls the mobile app poor and search nearly useless.

The mobile app's push notifications do not really work and returning to the app takes about 15 seconds to reload, which made it useless for this user.

Affects: mobile users

Affects: self-hosted admins on PostgreSQL

Affects: multi-team admins

Affects: admins using Apache reverse proxy

Affects: school running team edition with 2000+ users

Affects: large team edition deployments on OpenShift

Affects: infrequent users

Affects: team admins

Affects: small team on the open source edition

Affects: community edition admins

Affects: Firefox users

Affects: teams using webhooks and bots

Affects: self-hosters on iOS

Affects: personal / non-commercial self-hosters

Affects: desktop app users

Affects: privacy-minded self-hosters

Affects: Windows desktop users

Affects: Linux web users

Affects: users with non-QWERTY keyboard layouts

Affects: teams migrating from Slack

Affects: admins configuring GitLab SSO

Affects: contributors building from source

Affects: Docker admins using Office 365 SMTP

Affects: Free plan self-hosters on Firefox

Affects: non-English deployments

Affects: keyboard users

Affects: community operators

Affects: users with custom mention keywords

Affects: S3 storage users

Affects: Firefox private mode users

Affects: desktop app users

Affects: Mac desktop users

A fan of the product wants it to support the Matrix protocol natively for federation, or at least allow a native-looking third-party bridge.

A team on the open source edition has been without video calls and considers an alternative that offers them.

Affects: small team

The commenter wants the vendor to improve search, which they consider a critical feature in a company setting.

Affects: company users

A team that fully switched from Rocket.Chat says the Slack bridge they used there was wonderful and wishes an equivalent existed for Mattermost.

Affects: teams bridging to Slack

A FOSS community on the platform struggles to give support publicly because there is no good way to archive topics, and suggests a tool that lists popular threads on a public page.

Affects: open source community admins

Affects: admins running MySQL

Affects: Keycloak users

Affects: system admins

Affects: community members

Affects: CJK teams and teams using initials as usernames

Affects: web client users

After the vendor raised the price, a team dropped the paid plan and had a developer build a stand-in GitLab auth page connected to LDAP so the open core edition could authenticate against their directory.

Affects: team using LDAP auth

The mobile app cannot easily connect to both an internal company server and an external community; the vendor reportedly was working on it, and a stopgap is to sideload a second copy of the app.

Affects: users with internal and external communities

A commenter recommending self-hostable chat for open source communities says recent feature downgrades in the community edition take Mattermost out of consideration.

Affects: FOSS communities

A company found the self-hosted chat less smooth and more annoying, with occasional missed notifications, and preferred Slack's richer product.

Affects: company that self-hosted

The commenter says managing the chat server is not the company's core competency, which was part of the reason to move to a hosted tool.

Affects: non-IT company