Load GST videofilter plugins.
The video playback tries to create a videobalance element and can't find it without this plugin.
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WebGLSender doesn't really implement Serializable
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Add an API which turns a `WebGLSender` into something that is actually serializable.
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Add clipboard cut functionality
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This PR adds clipboard cut functionality. #23735
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- [X] These changes fix#23735 (GitHub issue number if applicable)
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