This filter is already documented in core/wp-includes/media.php
post_gallery
post_gallery-
action -
filter jetpack_infinite_scroll_load_scripts_and_stylesAllow plugins to enqueue all Infinite Scroll scripts and styles on singular pages as well.
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filter stats_arrayFilter the options added to the JavaScript Stats tracking code.
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filter atd_load_scriptsAllows scripts to be loaded via AtD in admin.By default, AtD only enqueues JS on certain admin pages to reduce bloat. The filter allows additional pages to have AtD JS.
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filter vimeo_heightFilter the Vimeo player height.
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filter vimeo_widthFilter the Vimeo player width.
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filter audio_player_default_colorsSet the audio player default colors.
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filter video_embed_htmlFilter the YouTube video HTML output.
Jetpack Developer Resources 