I acknowledge the warning when posting. At the risk of necroing a thread that is more than a whopping 120 days old, it's the first search result (this thread is much older than that, still... please don't turn this into another "Reddit"! it's so frustrating with duplicate posts on the same topic!), the main reason for joining was installing Lazarus - and the secondary reason to report here
That I, too, experienced a missing Source Editor window with nothing appearing under Center a Lost Window, nor anything wrong with the Left and Top coordinates mentioned. All normal.
I wanted to report my only
solution, which was by doing it the old Delphi way, by going:
Project > Project Inspector > click .pas file~
The rest of my post is for the devs. (I'm new, please inform me if I should open a ticket rather than write this in a random thread where it might not be seen.)
This is on Win7x64 with a single monitor.
The disappearing Source Editor (and Form) window thing happened for me when re-opening a sample project by going:
Tools > Example Projects... > Filter "scanline" > select first option > Open first selected
The first time I followed the above path, it worked perfectly.
Then I opened various sample projects and all worked fine.
At some point, the Source Editor just got hidden and I wouldn't see the source (or Form) window for
any project I opened. New Project worked fine all the time, but I was completely unable to open and see the .pas source in any project (except new ones). (I did try closing everything and starting Lazarus again, but it persisted.)
I'm not sure about the causality, but as a suggestion it may have happened after I tried to convert a Delphi project, which worked fine after translating SetPixel. I also used the JEDI code formatter, if that helps to nail this. Great features! :thumbsup: