AE 2018 Keyboard lag on Mojave
Just bought a new iMac - AE 2018 has a really frustrating keyboard input lag. Even if you type slowly it misses characters as you type (adding text or just using the interface i.e. naming folders, changing values, pressing spacebar etc). It's incredibly frustrating.
We really appreciate your post, however, User Voice is primarily for feature requests and bug reports. It appears your issue is more of a troubleshooting problem which could be solved more easily by our support team. You can open a case with them via call or chat at this link: https://helpx.adobe.com/contact.html
I can confirm that this is NOT a troubleshooting issue and is indeed a bug.
AE 2018, AE 2019 and AE 2020 all suffer from this problem. I have 12 new Mac Pros in the office that we bought earlier this year, and they all have this issue. It's an issue that happen on both single-screen and dual-screen layouts.
Whenever I type, AE 're-renders' the composition on-screen! After every single keystroke! So if a keystroke is pressed during the 'refresh' process, it ignores it. So typing is a MAJOR pain. I literally have to type one keystroke per second in order to ensure that AE recognizes all keystrokes.
Operating Systems on all computers here: High Sierra and Mojave
RAM: between 32 and 64 GB
GPU: Radeon Pro Vega 56