If anyone is interested in safely preserving food, the USDA provides the USDA's Complete Guide to Home Canning, which has recipes and canning guidance when using a pressure canner. Their current webpage is here:
https://www.nifa.usda.gov/about-nifa/blogs/usdas-complete-gu...
This page refers out to the National Center for Home Food Preservation, which is a web resource with similar guidance and recipes:
These recipes do include things like salsas. The point being is that safe canning practices have been well-studied, documented, and already paid for by tax payers. It's a good resource to use as opposed to just winging it.