UI glitches if multiple questionnaires are scheduled at the same time

[CedricReichenbach]

Observed symptoms (perhaps some are unrelated):

• Once a questionnaire has been committed, the next one doesn't properly appear (until a UI refresh happens, e.g. due to a resize, or turning phone) --> reproduced
• Some questions are posed multiple times --> reported, not reproduced
• In some cases, the questionnaire starts at the second page/question --> not consistently reproducable

[CedricReichenbach]

This might actually have been a glitch related to #86.

[CedricReichenbach]

Steps to reproduce:

1. Create two questionnaires, one with 3 questions, one with 1 question.
2. Schedule them at the same time, make sure the 3-qestions one is posed first (no enforced order, just try out).
3. When questions arrive, fill out the 3 of the first questionnaire, submit.

Expected result: Next questionnaire gets displayed.

Actual result: Only pagination dot is visible, otherwise blank white page: