doom widescreen texture name

[dummdoommapper]

so im currently making a doom mod that is similar to chex quest and I need your help to find the texture name of the widescreen bar of gzdoom because the widescreen bars is just there to fit the widescreen and I need your help to find it. here's an image:

[Kan3]

By "widescreen bar" you mean the border?

That is made up with "GRNROCK" flat.

 

You can directly change that texture with the BorderFlat property in a MAPINFO lump (GameInfo definition), or you can even get rid of it modifying the status bar with a SBARINFO lump or ZSCRIPT