There are plenty of shortcuts and tricks to get large layers to fit into a smaller comp.
But how about resizing a smaller comp to match a bigger layer? I'm looking for something similar to Photoshop "Reveal All" command that expands the canvas to fit all layers.
If the layer is a solid or footage you simply drag the asset from the Project Panel to the New Composition icon and you get a comp to match the asset. If the asset has a length and frame rate, the comp matches.
If you want to resize a comp you've already created to fit a larger asset then the best option is to use File>Scripts>Scale Composition. Just enter the new width. You can find the width by selecting any asset in the Project Panel and reading the width (first number) next to the Thumbnail preview. The script will also scale up any animations you have in the composition.
There's no single click solution or shortcut for matching a composition to an asset.
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