As a senior dev my role is to stay away from doing those tasks as much as possible. Well functioning organizations do not keep senior devs to do the stuff that junior devs can. My first task at a new team is to have a 1:1 with my manager to set our relationship properly and this includes laying out all expectations. Typically managers understand that it takes some time to get productive. Do not waste that time by doing tasks that do not increase your productivity. You should be learning the codebase, the development process, etc. Fixing bugs is one way to do it, but not necessarily the best. You may easily spend a lot of time on this, not gain much insight and actually not make a good impression as your colleague with much more experience will do it in 1/10th of the time. Also, starting on the right foot with the team is also important for your future productivity so it may be necessary to do some of those tasks anyway, but always remember that at the beginning your job is to build a good base for your future work.