I spotted another place where scientists disappear.
To reproduce:
* Start new game, place first base, enter base
* Enter "Research" - note 2 scientists available, leave
* Enter "Building", build quarters, leave
* Enter "Research" again - note 4 scientists available.
(they should be available in 4 days when quarters are finished)
** click "+"-button on any research topic - note 1 scientist working,
plus 1 scientist available - 2 of them just disappeared
** click "+"-button again - note 2 scientists working,
plus 0 scientists available
Issue 1535194 on sf.net, see
https://sourceforge.net/tracker/index.php?func=detail&aid=1535194&group_id=157793&atid=805242
