mobile app does not show barlines if extended when viewing only a single-lined instrument

To replicate:

1. Create new score with single instrument.
2. Add a single-lined instrument (e.g. 1-lined drum) or add any instrument and set to 1-line.
3. optionally add notes or a repeat sign
4. Extend a barline across all staves by double-clicking and dragging the bottom down.
5. Upload to musescore.com and open in songbook app or free app. (tested on android)
6. Only display the single-lined instrument by going to mixer settings and un-selecting the eye for 1st instrument. Observe that no barlines are shown.

Error occurs with 1-lined instruments (even non-drums), but not 3-lined or 5-lined instruments.

Note: musescore.com "PDF of all parts" and desktop "generate parts" correctly display the barlines in the part for the single-lined instrument.

(I also uploaded the attached example to secret link http://mus.cr/1JVOezT but please don't complain about that secret link not being "public", as I don't want to clutter my account with test scores.)