Logic Masters Deutschland e.V.

Normal Sudoku rules apply.

The digits outside the grid are Sandwich clues. They show the sum of the digits Sandwiched between X and Y.
The digits on the left are the sum of the digits between 4 and 6 on the rows.
The digits on top are the sum of the digits between 3 and 7 in the columns.
The digits on the right are the sum of the digits between 2 and 8 on the rows.
The digits at the bottom are the sum of the digits between 1 and 9 in the columns.

f-puzzle link

I recommended turning off the Highlight conflicts in the Settings