I was debug-running my project and then stopping it by clicking the Stop button on the IDE toolbar.
In the next moment my code looks like this:
Without saving it, I quit Xojo and logged out of OSX and in again. Upon re-opening the project, the code is readable again.
I tried to reproduce the issue, also with a new project, but I can’t.
If anybody else is seeing such a thing, please report.
If it happens again try Save As
Looks like an encoding issue.
are you using IDE custom font settings? I’ve had something familar with an older Xojo version and could track it down to a faulty Truetype Font.
Yes, I’m using Adobe Source Code Pro. I remember I had this issue with a previous version of the IDE, quite some time ago. It never happened again until now…
I also use it since long time ago. No issues:
just an assumption, lets see what Norman says…
hope its not that font… I too use it… its a very nice coding font.
It is obviously an encoding issue.
If it is the font, changing back to System should immediately show the text.
It could be a corrupt font though, in which case the system just picks another one. If that font were a symbol font with no characters, you might get this.
I havent had issues with that font on neither Windows nor Mac.
Doesn’t that mean you HAD issues with the font on BOTH Mac and Windows? 
FWIW I use the “Hack” font - it’s very nice as well. Never had a problem like @Oliver Osswald describes.
Wow. I do not like the zero in Hack.
I use Menlo, no problems here.
No. Unless my Boolean logic in my English is off.
Interestingly enough, the question mark character showing in the editor in the screen shot in the OP is neither part of System Regular on 10.11, nor Source Code Pro ; as if it was coming from another font altogether.
But apparently Oliver has also been abducted by extraterrestrials since that post
[quote=258785:@Michel Bujardet]Interestingly enough, the question mark character showing in the editor in the screen shot in the OP is neither part of System Regular on 10.11, nor Source Code Pro ; as if it was coming from another font altogether.
But apparently Oliver has also been abducted by extraterrestrials since that post ;)[/quote]
Ahem…?
It is not for the first time that I ran into this issue with Xojo, but as I can’t reproduce it, it won’t be fixed. Nobody came up with some information that would help to change this. So?