This means the crop toolbar button is not visible you can still access the mode by pressing C on the keyboard. The only difference is the top toolbar, which uses the standard Photos app extension interface with Cancel and Save Changes buttons.

The Photos interface transforms into the Pixelmator Pro experience.

extension button in the top-right toolbar, and select Pixelmator Pro.

With Pixelmator Pro 1.4 installed, find an image in Photos and enter Edit mode. Of course, edits and changes are saved nondestructively and synced with iCloud. All the Pixelmator Pro keyboard shortcuts work too. You can access all the same selection, effects, and drawing tools from the main app. And Affinity has enough of those 'key features' that someone could realistically not need Photoshop. You are essentially getting the full power of Pixelmator Pro inside of the Photos app. Affinity Photo is like Pixelmator in that both have 'fewer features' than Photoshop, but Affinity Photo has more of the 'key features' of Photoshop that Pixelmator does not have and I think Affinity is the stronger competitor by far. It’s certainly the most ambitious editing extension for Photos that I have seen. All layers, effects, and adjustments are available in the extension. This means you don’t have to launch a separate app to perform complex edits when browsing your library in Photos.

Impressively, the entire Pixelmator user interface is now available as a Photos editing extension. The Pixelmator team today released an update to their premier Mac app, Pixelmator Pro, with a new app extension, new zoom tool, updated crop options, and more refinements.

Affinity vs pixelmator