How to get the information from a meta tag with JavaScript?

To get the information from a meta tag with JavaScript, we use the content property.

For instance, we write

const content = document.head.querySelector(
  "[property~=video][content]"
).content;

to select the meta element with the property attribute containing video and has the content attribute with document.head..querySelector from the head element.

Then we get the content attribute from the selected element with the content property.