All the cover letters I have written have flown over the head of the application reviewers, they didn't even glance at it on all the interviews where a cover letter was required in the application form, the interviewer always asks the same questions that I already answered in the cover letter. funnily enough, all the companies that I had applied also didn't bother looking at my github account even to 'github account link' field in the application form is supposed to be there for some reason