A missing value "allow-downloads-without-user-activation" was also added.
The display attribute doesn't accept "initial" as value, which is a value all css attributes can have. Here it is added. Also "initial" is always the default value for a attribute, so it was changed to be the default here too.
The previous default was "block", which is wrong accourding to https://developer.mozilla.org/en-US/docs/Web/CSS/display#Specifications.
As stated in https://developer.mozilla.org/en-US/docs/Web/HTML/Element/iframe#attr-referrer the sandbox attribute can now take multiple argumens in the form of an array. The array is converted a space-saparated list.
A missing value "allow-downloads-without-user-activation" was also added.
The display attribute doesn't accept "initial" as value, which is a value all css attributes can have. Here it is added. Also "initial" is always the default value for a attribute, so it was changed to be the default here too. The previous default was "block", which is wrong accourding to https://developer.mozilla.org/en-US/docs/Web/CSS/display#Specifications.