I am not comfortable that signal depends proprietary google library. However, I find that Molly lags significantly behind signal (around 1 to 2 weeks, so maybe not as significant as I thought), but I am just concerned that if there is a security fix in signal, molly will not be able to react as fast.
I am also quite frustrated with the general lack of communication from the signal team (for example the lack of communication regarding username). I doubt they will have the good will to help molly when there is a critical security fix.
It is frustrating that signal no longer seems like the gold standard for privacy any more; unfortunately, all my friends are on there (ironic, isn’t it…).
AFAIK, they have a FOSS variant
To support a 100% free and auditable app, Molly comes in two flavors: one with proprietary blobs like Signal and one without. They are called Molly and Molly-FOSS, respectively. You can install the flavor of your choice at any time, and it will replace any previously installed version. The data and settings will be preserved so that you do not have to re-register.
Also the line right after your quote:
Versions
Molly, like Signal, uses Google’s proprietary code to support some features.
Molly-FOSS is the community effort to make it 100% free and open-source.