fix(rrweb-snapshot): don't exclude @import CSS rules from the output when an exception is thrown

[hvpavel]

Do not exclude @import CSS rules from the output when an exception is thrown and use CSSRule.cssText instead.

rrweb-snapshot throws a SecurityError exception when parses @import CSS rules, that point out to an external domain and are declared within a CSS file.

page.html:

<link rel="stylesheet" href="styles.css" />

styles.css:

/* this rule will be excluded from rrweb-snapshot output */
@import url('https://fonts.googleapis.com/css2?family=Open+Sans&display=swap');

The fix is meant to fix this problem and keep the original CSS line if another issue happens while serializing an @import CSS rule.

A repository with an example of the issue: https://github.com/hvpavel/rrweb-snapshot-css-import-issue.

[Yuyz0112]

Thanks!

[hvpavel]

@Yuyz0112 thanks for accepting the fix. Could you please tell me when you will be able to publish a package with the fix?