An open-source extension with closed "All Rights Reserved" license?

Claims to be open-source but it's not: https://github.com/WorldBrain/Memex/issues/1229#issuecomment-1079614623

Has bugs. Has limits in the free version, and you must create an account and become a paid member to lift them.

Buggy and annoying.

Unable to export my data or links. They made a mess by automatically importing all my bookmarks without any consent.

Hijacks my YouTube video pages with unnecessary stuff that I am not able to disable.

I'm a pleb so i rely on UX and statements of intention to indicate whether a project is actually privacy/self-hosted/encryption guided. This UX was very bookmarks grabby pre-account creation and their notion post indicate they're going the notion/polar route of starting open source, also willing to reconfigure their paying subscribers designations ~fatally flexible principles for a project aiming at a powerful techform.

Gmail doesn't work with this add-on.
Contact can't connected.

最新版本还是没有解决CPU占用过高的问题，已弃用。。。
The latest version still does not solve the problem of high CPU usage~ deprecated. . .