Videos slow down page load

The gallery is not slowing down page load, but preloading many videos might.

Go to video gallery settings > Miscellaneous > and set Initialize on to scroll and now the gallery will initialize when the gallery is visible

IN the shortcode make sure init_on is set to scroll

Go to video gallery settings > Play options > and set Cue First media to Disabled

In the player configuration you are using set preload method to none

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