Arduino IDE won't start when sketchbook folder is set to Arduino IDE installation folder

Hi developers! Thank you for this magical product!

If I install the Arduino IDE in the latest Ubuntu Studio via the Snap Store, everything works fine. If I install the Arduino IDE on Xubuntu 18.04.4 by downloading arduino-1.8.13-linux32.tar.gz and unpacking it into the arduino-1.8.13 folder (then ./install.sh from root and ./arduino-linux-setup.sh ), everything works fine.

If in latest Ubuntu Studio download arduino-1.8.13-linux64.tar.xz, then extract and move to ~/Arduino folder, Arduino IDE starts normally. After closing, the second time does not start, only shows a splash image for a second and does not start. If I erase ~/.arduino15, the IDE starts normally again, but only once. However, it is impossible to find information in the log files that the program did not like. As a result, it turned out that it was necessary to select a folder for sketches in File - Settings that is different from ~/Arduino, then everything starts working fine.

There is a suggestion when such an event occurs, display a modal window with a proposal to select a separate folder for sketches.

Thank you!

Reproduce the failure in the extracted Linux IDE by setting the sketchbook folder in File - Settings to the IDE installation folder, then restarting it. Inspect the startup behavior and ~/.arduino15 configuration or logs; done means the IDE starts reliably or presents a modal prompt to choose a separate sketchbook folder.

Written by the indexing model from the issue text.