XMPP Compliance Suites 2022
XEP-0459 describes XMPP Compliance Suites 2022. Here, I try to evaluate Gajim's state of compliance.
Gajim seems to meet the requirements to be a 'Core Client' in the 'XMPP IM Compliance Suite.
In order to meet the requirements of 'Advanced Client', the follwing XEPs are missing:
Advanced Group Chat: XEP-0410: MUC Self-Ping (Schrödinger's Chat)
Persistent Storage of Private Data via PubSub: Best Practices for Persistent Storage of Private Data via Publish-Subscribe (XEP-0223)
Direct File Transfer XEP-0261: Jingle In-Band Bytestreams Transport Method