@trustedScriptlet trusted-set-attr
@description
Sets the specified attribute on the specified elements. This scriptlet runs
once when the page loads then afterward on DOM mutations.
Reference: https://github.com/AdguardTeam/Scriptlets/blob/master/wiki/about-trusted-scriptlets.md#-%EF%B8%8F-trusted-set-attr
@param selector
A CSS selector for the elements to target.
@param attr
The name of the attribute to modify.
@param value
The new value of the attribute. Since the scriptlet requires a trusted
source, the value can be anything.
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Additionally, start to move scriptlets into their own source files
for easier maintenance and code review.