Illustrator creating shape out of lines

[linsy_raens]

Hi, I have the latest update and a new powerful computer, but I noticed that lately Illustrator is creating these weird shapes to sharper corners. When I change the path they dissapear. It always appears in the corners. Luckily they do not appear when the artwork is saved. But it just bothers me as I design a lot of smaller icons and there are quite a few of these gliches.
Any ideas why is this happening?

Added a screenshot below:

[Doug A Roberts · Accepted solution]

Do they disappear if you change to View > Preview on CPU?

[linsy_raens]

Ah yes ... I selected Preview with CPU and they dissapearred. Was that my issue? Using wrong preview?

[Doug A Roberts]

It's more an issue with Illustrator than you doing anything 'wrong'. It indicates that it is a purely visual bug.