There was an error trying to redefine variables from l10n.js via loadSubScript. We really only need it loaded once like a frame script but I had to fix the l10n.js code to handle this properly. MozReview-Commit-ID: EbNrEaRQJbs
MozReview-Commit-ID: GUX3Gia293X
MozReview-Commit-ID: 9f0vPciw65V
MozReview-Commit-ID: LjrRXr1thc8