Posting this mainly to keep it for myself, but making it public to benefit anyone else looking for it as well.

By default, SciTE‘s open dialog box is set to “All Source,” which means to show a list of all files it considers “source files” (files that contain program source code.)

I wanted my copy of SciTE to display “All Files” in the open dialog box by default, and then I could select “All Source” if I wanted that more narrow selection.

To do this, I opened SciTE, navigated to the menus Options -> Open User Options File, which opened ~/.SciTEUser.properties and I added this one line:

top.filters=$(all.files)All Source|$(source.files)|

This specifies that it should use the $(all.files) filter by default, then show the “All Source” option, then all the individual $(source.files) options (Ada, Bash, C++, etc.)

FYI, $(all.files) is defined as the following, depending on platform (I use a Linux distribution, so my platform is PLAT_GTK):

# Each platform has a different idea of the most important filters
if PLAT_WIN
	all.files=All Files (*.*)|*.*|
	top.filters=All Source|$(source.files)|$(all.files)
if PLAT_GTK
	all.files=All Files (*)|*|Hidden Files (.*)|.*|
	top.filters=All Source|$(source.files)|$(all.files)
# As OS X only greys out filtered files, show all as default
if PLAT_MAC
	all.files=All Files (*.*)|*.*|
	top.filters=$(all.files)All Source|$(source.files)|