How to fix Missing plugin: gstreamer on Ubuntu 18.04 Bionic Beaver Linux -

The follow error message appears when trying to play video or audio: Message: Missing plugin: gstreamer|1.0|totem|MPEG-4 AAC decoder|decoder-audio/mpeg, mpegversion=(int)4, level=(string)2, base-profile=(string)lc, profile=(string)lc (MPEG-4 AAC decoder) Message: Missing plugin: gstreamer|1.0|totem|H.264 (Main Profile) decoder|decoder-video/x-h264, level=(string)3.1, profile=(string)main (H.264 (Main Profile) decoder)
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