Adobe Illustrator 22.0.0, Mac OS 10.11.6 - Extensis Universal Type Client user:

I am experiencing a very troublesome bug:
- make a text box with a few lines
- put a backgrund coloured object under it, so that multiply blending can be shown up easily when applied
- apply a blending mode (such as multiply) to the second line only; now you have a single text box where the first line is normal, the second is in multiply mode
- save the file
- re-open it: the multiply text line has reversed to normal mode

This also happens if you apply a second fill in the aspect palette and made it multiply (or other blending modes).