Frontend exception on undefined macro

On macOS 11.6.1 on M1 MBP 13 using OF 0.11.2 release PG.

The Electron frontend throws an exception when parsing macros in config.make while importing an existing project:

Exception backtrace copy/paste:

Uncaught Exception:
TypeError: Cannot read property 'length' of undefined
at /Users/danomatika/src/of/of_v0.11.2_osx_release/projectGenerator/projectGenerator.app/Contents/Resources/app/index.js:577:30
at Array.forEach (native)
at EventEmitter.<anonymous> (/Users/danomatika/src/of/of_v0.11.2_osx_release/projectGenerator/projectGenerator.app/Contents/Resources/app/index.js:556:30)
at emitTwo (events.js:87:13)
at EventEmitter.emit (events.js:172:7)
at EventEmitter.<anonymous> (/Users/danomatika/src/of/of_v0.11.2_osx_release/projectGenerator/projectGenerator.app/Contents/Resources/atom.asar/browser/api/lib/web-contents.js:54:23)
at emitTwo (events.js:87:13)
at EventEmitter.emit (events.js:172:7)

This appears to be due to some custom makefile stuff added to the end of the affected config.make.

Without looking into detail, adding an undefined check for the macro variable to https://github.com/openframeworks/projectGenerator/blob/master/frontend/index.js#L577 allows the PG to finish importing the project successfully:

if(macro !== undefined && macro.length && value.length){

Start in frontend/index.js around line 577 and reproduce the failure by importing the linked loaf project, whose config.make contains custom makefile content near its end. Trace the macro parsing that produces the undefined value and verify that importing the project completes without an exception after the fix.