">0.25%"value tells [Browserslist] to only [target] browsers that make up more than 0.25% of global usage. This ensures your bundle does not contain unnecessary transpiled code for browsers that are used by a very small percentage of users.
In most cases, this is a better approach than using […] the
"last 2 versions"value[, which targets] the last two versions of every browser, which means support is provided for discontinued browsers such as Internet Explorer. This can unnecessarily increase the size of your bundle if you do not expect these browsers to be used to access your application.
Ultimately, you should select the appropriate combination of queries to only target browsers that fit your needs.
Can I use… is an invaluable resource that we all (hopefully) use on a regular basis, but what if you have an existing codebase that you want to evaluate for browser support? You could go through it manually, but that could be a lot of work. Thankfully, someone has put together an app and a Node.js module that can crawl your CSS and list what will break in what browser.