I found this outstanding G Code Editor made specifically for 3D Printing.

It organizes the code by Z Axis layer height. Then the code for a specific layer is in a separate column window. In a third window is a graphic representation of the code that is highlighted in either of the code windows.

It is quite an amazing piece of software.

It is a little difficult only because Shafri is using a totally different approach. You will have to get out of your box.

The program is a stand alone executable. It layer column was not wide enough to display my my huge G Code files. I sent him some cash via PayPal and he was prompt in fixing the bug. It will not show up on his web site for a while so if you message me I can send it to you.

http://www.soasystem.com/download/r3dgedit/
https://reprap.org/forum/read.php?1,374302

This helped me change some rapid moves in a complex print that exceeded the processor speed of my printer.

About open Source Software.....
We all spend tons of money printing things that are cool but of questionable value. So how about that you donate some money to these developers that make your hobby possible.
While researching Marlin which runs most of our printers, I found that there is one guy maintaining the cornerstone of our hobby.
He is sort of begging for money so he can develop Marlin full time. I think every manufacturer should donate at least $10 for every printer they sell with Marlin. But they do not.

Marlin is actually used less than Repetier firmware. Repetier has been the standard for many years while Marlin has only been catching on the last 5 years or so..

It organizes the code by Z Axis layer height. Then the code for a specific layer is in a separate column window. In a third window is a graphic representation of the code that is highlighted in either of the code windows.

It is quite an amazing piece of software.

It is a little difficult only because Shafri is using a totally different approach. You will have to get out of your box.

The program is a stand alone executable. It layer column was not wide enough to display my my huge G Code files. I sent him some cash via PayPal and he was prompt in fixing the bug. It will not show up on his web site for a while so if you message me I can send it to you.

http://www.soasystem.com/download/r3dgedit/
https://reprap.org/forum/read.php?1,374302

This helped me change some rapid moves in a complex print that exceeded the processor speed of my printer.

About open Source Software.....
We all spend tons of money printing things that are cool but of questionable value. So how about that you donate some money to these developers that make your hobby possible.
While researching Marlin which runs most of our printers, I found that there is one guy maintaining the cornerstone of our hobby.
He is sort of begging for money so he can develop Marlin full time. I think every manufacturer should donate at least $10 for every printer they sell with Marlin. But they do not.