SQL Developer started off-screen (Windows 10), and I couldn't get Size & Move to fix it.
I have 2 side-by-side monitors, and after an office shift, the monitors were re-assembled reversed. I rearranged logical displays in Windows and reversed displays 1 & 2. This was no problem to other apps (e.g. Chrome, Edge, Explorer, GitEye, Notepad++, VS2017, Word, Outlook etc).
However, SQL Developer now seemed to be loading to the left of the left monitor. I tried Size and Move from the task bar, but couldn't 'get traction' on the off-screen window. Toggling between Restore and Maximize resulted in it showing full-screen and then not at all.
Eventually I managed to get it back via [Windows]-D, but it was a pain to try various fixes to get it back, when other apps had no problem.
Could someone maybe could look into fixing SQL Developer so that it handles this situation better e.g. like other Windows app ?
SQL Developer (Version 188.8.131.527, Build 277.3454), Windows 10, 2 x side-by-side monitors 1920x1080 (BTW unable to change screen resolution, which is another recovery procedure)
Did you try using the reset windows layout ?