I just found a WAY faster way than doing the jigsaws legit.
I created a short video that should help reproducing this method:
The process of doing an expert (or any difficulty) jigsaw in roughly 2 minutes is pretty simple:
0. This method only works on freshly started jigsaws. If you move a tile before using this method it will still kinda work for most tiles but some may be in the wrong place. (Thanks to Tazmad7 for pointing at it)
1. Open an jigsaw
2. Press the "lock view" button
3. Select all tiles
4. Grab the lower right tile and move your mouse to the top left of the screen and let go. All tiles should be on one big pile now.
5. Select all again and move the pile to somewhere you can access it nicely
6. Take the top piece and move it down one tile and let go. It should snap to the tile that is now on top.
7. Take the 2 snapped tiles and move them down one tile again and it should snap to the top tile again.
8. Repeat step 7 until you have a complete column of pieces and move it to the right. That should be the right edge of the jigsaw.
9. Now repeat 7 and 8 until you have the next column complete and snap it to the column you already have.
10. Keep repeating until the puzzle is complete
This is ridiculous