We're aiming for deterministic package installs and using the tools the package manager,
npm, provides. Please install npm v7.x (not lesser or greater). For a consistent package state, try starting with:
npm i -g npm@7 rm -rf node_modules npm install
Upgrading a package (or adding a new one) should go as follows:
node --version # should give you 12.x or above npm --version # should give you v7.x or above npm i firstname.lastname@example.org --save(-dev) # git review
Now everyone's happy and the patch got merged.