Issues with klimerko.org site

I've found a couple of issues/bugs with the klimerko.org site:

There is no valid SSL certificate for parts of the site (at least for me in the newest Firefox) and the browser keeps reminding me that the connection is not secure - this should be an easy fix
On the map there are only PM10 values visible, for PM2.5 you need to click on each of the stations to get a more detailed view. It would be beneficial if there were some switches on the map viewer where you can choose PM10, PM2.5, temperature, humidity, etc. to be shown in the circles on the map for each station. In the current state, UX is really not that great, because you are losing a lot of time trying to find out what you want. For example, if you want to find out PM2.5 values in some specific city, you will need manually to go to each individual station and click for more details, and then look for PM2.5 values. This could be avoided if there was a way to have PM2.5 values in the circles on the map when you are scrolling/searching through
Data on the left panel are maybe not be needed, or at least, some sort of header for that table or explanation of what they are would be nice. Maybe it would be better if this panel is hidden by default, with an option to expand the panel
There is a bug when you open/click on one of the stations, and then close it. Instead of returning you to the point in the map where you've been, you are redirected back to Belgrade (see attached .gif for an example)

Bug reproduced: better quality

On detailed view of the station, there is no scrollbar, and if you open this page on older devices or if it is zoomed in, you cannot see the measurements that are below the main (visible) portion of the section

DesconBelgrade / Klimerko