Revach.net: Succah Decorations That Were Made For Non Jewish Holidays
Decorations: Many communities decorate the Sukkah with colorful posters depicting holiday themes on the walls or by hanging fresh fruits or other decorations from the sechach beams. The Chabad custom is not to decorate the Sukkah, as the Sukkah itself is considered to be an object of beauty.
Breslov Minhagim / Customs and Spiritual Practices (Elul‐Chanukah):
It is common practice among Breslover Chassidim to decorate the Sukkah. Most hang fruits and other objects from the s’khakh, according to their family minhagim. There does not seem to be any hakpeidah to refrain from hanging things from the s’khakh due to chumros.
(Heard from Rabbi Avraham Shimon Burshteyn)
Rabbi Riddle: Chassidic Sukkah Decorations!