App Designer unable to read a temp MAT file?

I've been working on an app in App Designer for a few weeks with no issues. Today, having not changed the code at all since I last successfully opened and ran it, I started getting this error when I try to open the .mlapp file in App Designer:

"Unable to read MAT-file /tmp/tpc4fb489a_d48a_4ef2_86d2_73ba85e1356d.mat. Not a binary MAT-file. Try load -ASCII to read as text."

Where the long filename is something different every time.

This temp MAT file isn't something I wrote; I assume it's some internal MATLAB functionality, but I don't really know what it's doing or why it's suddenly causing an issue. How can I can fix this?

[Walter Roberson]

Double check in case /tmp file system is full.

[Anna Barth]

I wasn't sure how to check if /tmp is full -- I can't actually find it in my file system (I think it's deleted when not in use?)

I did try changing my tempdir using setenv('TMP','/newtemp'), such that now a call to tempdir returns '/newtemp/'. Now, when I try to open my file in App Designer, I get a new error:

"Data was not captured properly from 'path/to/my/project/filename.mlapp'."

[Walter Roberson]

 ! df /tmp

[Anna Barth]

Okay, so in the time since I last tried, MATLAB mysteriously starting giving me a third, new error. I gave up and reverted to a slightly older version of my .mlapp file. It works fine now -- I think the file got corrupted or something. Thanks for your help!

[Chris]

I am seeing exactly this with R2024b, and it's blocking my work. Is there a work around?