From Michael Cammer via the ImageJ mailing list:
In standard ImageJ, each text window is easily accessible from the Window menu. We can select it and then do commands such as:
selectWindow("20200725_rawdata.txt");
textdump = getInfo("window.contents");
a = split(textdump);
However, in Fiji, the text windows are in the Java text editor, are not listed in the windows menu, and getInfo("window.contents") returns an error that no window can be found.
Therefore, macros we have written for ImageJ with text windows don't work.