vp9parse: Fix critical warning during caps negotiation
gst_pad_get_allowed_caps()
returns a non-writable caps, so we need to make it
writable, otherwise the gst_caps_remove_structure()
call below might trigger a
critical warning.
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gst_pad_get_allowed_caps()
returns a non-writable caps, so we need to make it
writable, otherwise the gst_caps_remove_structure()
call below might trigger a
critical warning.