The mouse cursor disappears when running on Macbook Pro plugged in external 4k Display.
The same happens with a fresh install.
My Sublime version:
Here a video that a recorded to demonstrate.
Also I found a clue about what is going on.
When using the 4k scaled them mouse cursor vanish.
However, when using 1920x1080 which is doubled pixels, it works great.
It is annoying not been possible to code as I like using a scaled resolution 
This appears to be a bug in 10.13.4, from what I can tell ATM:
I’ll try to keep an eye on those to see if some sort of “fix” is found. Alternatively it seems some of those issues have workarounds that may help.
As a further bit of info, for dark background, we create a custom inverse I-Beam cursor using https://developer.apple.com/documentation/appkit/nscursor/1524612-initwithimage?language=objc. All other cursors we use are built-into the OS.
This makes me believe a bug exists in regards to custom cursors with external displays. This is probably also why a bunch of other applications using editor like controls with dark backgrounds are seeing the same thing.
Here is the GitHub issue for the problem: https://github.com/SublimeTextIssues/Core/issues/2250
A workaround is to increase the cursor size a touch. System Preferences > Accessibility > Display > Cursor Size.
Glad I am not alone! Increasing the slight slightly breaks the screenshot button, increasing it further along bring it back. Long live giant cursors!
I just hope we get a fix soon.
+1 for this. I noticed that it seemed to be a resolution thing, and noticed that it was on my external screen, but did not think to increase the cursor size as a fix.
Works as fix for 10.13.4 High Sierra…keeping my fingers crossed for an update in 10.13.5.
