Custom Editor has stopped working

Hi. Yesterday I started learning how to create custom editor in inspector. It was going well, until about an hour ago, when my Unity crashed. It crashed when I changed a rectangle width of the IntSlider(don´t know why). Since then my custom inspector doesn´t even show(the script uses the default inspector design). I tried to fix it. I also tried creting a new editor script in new project and restarting Unity, but it still doesn´t work.
Any ideas how to fix this?

Ok, thanks for responses. I solved the problem. I seems like the editor script got corrupted or something after crash. I made a new editor script and copy/pasted my script.
Other editor scripts didn´t work, because I didn´t know that the class name must me the same as the name of the editor script.