Slice the onion thinly, fill with water and add a small amount of sugar and vinegar for 15-20 minutes (the marinade should taste tart). Cut the salad by hand into pieces or cut into strips. Cut the cucumber into half circles, pepper into thin strips, chop the greens. Put the onion on a sieve and let it drain well, you can even squeeze it out slightly. Mix all the ingredients carefully in a deep salad bowl.
