Today, I've left my laptop on, with Lazarus running. When the battery got empty, the Windows 10 did a shutdown, just as expected.
After starting the laptop again, the Lazarus installation was messed up to the point that I could not start Lazarus anymore. I got the dialog where it says something about the configuration, and at clicking on Next it just got stuck (tried á couple of times).
Installing Lazarus over the existing installation didn't help.
Next step, rename the directory c:\Users\{user_name}\AppData\Local\lazarus\ got me to the clean Lazarus without my settings and installed components.
Inspecting the old files (before re-installing Lazarus) from that directory - the file environmentoptions.xml was 64kb in size, but full of zeros. Other files in the directory seems to be OK.
I wish that Lazarus could be more resistant to such forced shutdowns.