Based on our record, osTicket seems to be a lot more popular than Phabricator. While we know about 38 links to osTicket, we've tracked only 3 mentions of Phabricator. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
My company has used Phabricator, which is an alternative to Azure Devops, for about 5 years. A few days ago they announced that the project won't be maintained anymore, so we are looking into alternatives. We have around 50 devs+product folks that use Phabricator at the moment. Source: about 3 years ago
You also mention Gitlab is close to what you would like - maybe Phabricator is even closer: https://phacility.com/phabricator/. Source: about 3 years ago
Https://phacility.com/phabricator/ I think checks most of those boxes, maybe all. Source: about 3 years ago
You can try osTicket https://osticket.com The UI is very tho dated, but we're working on a rewrite with modern UI. - Source: Hacker News / 9 months ago
Check out https://osticket.com/ I used earlier on my career. It’s free to use it worked great for a small team and it has everything you need. Source: 11 months ago
We use https://osticket.com/ It's not a groundbreaking ticket system but it's rock solid, user-friendly, and free. Source: about 1 year ago
Another option, for a dedicated ticketing/helpdesk system, is osTicket. Self-hosted is completely free, and I had it up and running inside of an hour, from creating a fresh Debian LXC, installing Apache/MariaDB/PHP8.1, and uploading the requisite files for osTicket followed by the initial setup. Going off your mention of snaps, I'm assuming you're on Ubuntu or a derivative, if you'd like I should be able to... Source: about 1 year ago
GLPI (https://glpi-project.org/) or osTicket (https://osticket.com/) are open source ticketing systems but I highly doubt they're what a MSP need. You need a PSA. Source: about 1 year ago
GitLab - Create, review and deploy code together with GitLab open source git repo management software | GitLab
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
BitBucket - Bitbucket is a free code hosting site for Mercurial and Git. Manage your development with a hosted wiki, issue tracker and source code.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.