Large repos can turn the command prompt unresponsive for long stretches of time.

This is due to the fact that the call to

git status --porcelain -b

can take a large amount of time:

 time  git status --porcelain -b
--- some data --
real    4m1.149s
user    3m59.189s
sys     0m1.948s

This makes oh-my-bash unusable. The prompt should ideally not be delayed for more than 0.1s. See https://www.nngroup.com/articles/response-times-3-important-limits/