While L1 has empty flash cell erased to zero, at least F1/F4 are erased to 0xff.
[fw/stlink] / nbproject /
drwxr-xr-x   ..
-rw-r--r-- 1392 Package-Default.bash
-rw-r--r-- 1406 Package-flash.bash
-rw-r--r-- 20827 configurations.xml
-rw-r--r-- 940 project.xml