I have been caught out a few times by committing files larger than 100mb, which throws an error when uploading to Github. This then involves a complicated filter-repo process to remove the files from the git history.
I found Git-Status-Size which checks the size of the files in git status and then prompts the user if they want these files to be added to .gitignore. This is a great idea, but I use Git Bash for Windows, which does not include the bc command to do calculations. Therefore, I have adapted to it now use awk instead.