In Pixelmator 3.4, we added support for the Force Touch trackpad when using various brushes, for example with the Eraser Tool or the Brush Tool. We noticed it wasn't all that intuitive for most people so, with version 3.4.1, we've decided to remove it for now. But, we left a (secret) way to turn it back on. Here's how to do it:
1. Quit Pixelmator
2. Open Terminal
(To do that, you can press the Command-Space keyboard shortcut to open Spotlight Search, then start typing "Terminal" and press the Return key when Terminal comes up)
3. Paste "defaults write com.pixelmatorteam.pixelmator PXMEnableForceTouchPainting -bool yes" into Terminal and hit Enter
4. Launch Pixelmator
Don't worry, you don't need to know anything about the Terminal app to do this and you won't break anything. It's just a different way of changing the settings in Pixelmator.
As always, if you have any issues with this or Pixelmator in general – we're here for you. Just drop us a line at firstname.lastname@example.org and we'll get right back to you.