All the websites I test have web analytics tracking that I need to block during runtime (we use dynamic loading of page resources, so I can't just delete them from the Virtual User profile).
I never use any of the default exclusions listed (.*\.jpg and .*\.jpeg etc.), and it's a bit of a pain to have to delete them all and then rewrite my exclusions into every scenario.
Is there a configuration file that I can modify to get rid of the preloaded exclusions and put in my own?
The default preloaded exclusions list cannot be modified as it is hard coded. But your can remove all the items at once. You can multiple select them and click on the "-" button.
I understand that if you have a specific list of filters to create for different scenarii it can take a long time since you will have to create them one by one.
Note that if you duplicate a scenario, the url exclusion list will also be duplicated.
I would also suggest you to enter an idea on our community web site in order to have a way to import/export a list of regular expression.