DuckDuckGo Browser is a webview browser which has weaker tab isolation and uses the system's default webview implementation, most often chrome webview.
Ubuntu is a corporate/popular distro. It wouldn't make much sense to move to do as when it lacks much of the functionality of sudo and isnt in a memory safe language, which is Ubuntu's goal with replacing user space software with Rust.
Canvas blocker is redundant with Librewolf's protections (privacy.resistFingerprinting), same with JS blocker redundant with uBlock Origin. You make yourself more fingerprintable. It is better that you first understand what protections you have and why before adding new addons that increase attack surface. The features you are looking for are included already.
Is there?