### Steps to reproduce

1. Enter a work package

2. On either Overview or Activity tab, scroll down

3. While scrolling you see the bottom action bar with the green button to leave a comment

4. Scroll down until the end


### What is the buggy behavior?

* Bottom action bar disappears and user must scroll up in order to leave a comment


### What is the expected behavior?

1. Bottom action bar should be sticky so that users can always leave comments without unnecessary scrolling up


**OpenProject version**

v1.1.0-alpha (214)

Begin of the insertion<br>End of the insertion Begin of the deletion **Operating System**

* [ ] Windows
* [ ] Mac OS X
* [ ] Mobile iOS
* [x] Mobile Android
* [ ] Linux (please specify distro)
* [ ] Chrome OS
* [ ] Other (please specify)End of the deletion