I've encountered some Front End behavior that I find mystifying.
I have created an ordinary Mathematica notebook that consists of a series of cells formatted as Code that each hold an expression that returns a result (typically a variable assignment). However, when I save this file as a notebook, *.nb file and then close it, upon reopening all the lines formatted as Code have been changed to a single cell formatted as Input with Inline input and ouput tags being preappended before each expression or its output.
Consequently, since most of my lines are long lists containing data that I am reformatting, the Front End becomes unresponsive when displaying the single long input cell and the file becomes almost impossible to edit.
I suspect I have inadvertently altered some notebook editing options or performing some kind of undesirable initialization but have no clue as to what might need to be reset to restore normal editing/saving/opening behavior.
What do I need to do to control this anomalous saving behavior so that I can readily execute my code upon reopening the file?
I am running Mathematica Vers. 126.96.36.199 on a Windows 10 64 bit machine.