Web Scraper uses css selectors to find HTML elements in web pages and to extract data from them. When selecting an element the Web Scraper will try to make its best guess what the CSS selector might be for the selected elements. But you can also write it yourself and test it with by clicking "Element preview". You can use CSS selectors that are available in CSS versions 1-4(that are supported by the browser) and also pseudo selectors that are additionally available in jQuery. Here are some documentation links that might help you:
It is possible to add new pseudo CSS selectors to Web Scraper. Right now there is only one CSS selector added.
CSS Selector _parent_ allows a child selector of an
Element selector to select the element that was returned by the Element selector. For
example this CSS selector could be used in a case where you need to extract an
attribute from the element that the Element selector returned.
A custom written CSS selector can be used to select elements within an iframe or shadow-root.
To select data within iframe create a selector that would select the
iframe element and then afterwards add :iframe. For example:
iframe:iframe .selector-within-iframe
Similarly a custom CSS selector can be used to select elements within a shadow root.
First select the shadow root parent element and then add :shadow-root to
the selector.
For example: .shadow-root-parent-element:shadow-root .selector-within-shadow-root
