Glyph Construction (UI and Python) adding unexpected blank glyph to fonts (RF4)

[arrowtype]

When I run Glyph Construction (either via the UI extension or via Python), it seems to add an unexpected blank glyph to fonts, like this:

This is showing a blank glyph because an empty string is added to the lib.plist withinpublic.glyphOrder and com.defcon.sortDescriptor[ascending]:

This has happened in multiple, very different fonts, so I don’t think it’s something from my particular files.

Versions:

• RoboFont 4.0
• macOS 10.15.5

[nicksherman]

I ran in to this issue as well, and realized it happens whenever there is any new line that is not a comment but is otherwise blank. I don't believe this has always been an issue, since my .glyphconstruction files have always had many blank lines but I only started getting the empty glyphs recently.

As a temporary half-fix you can add # to the start of any otherwise blank line to prevent it from resulting in a new empty glyph, but I agree the previous behavior was preferable.