Apr 2022 (updated in Jan 2023)
The photo Tiger 131 picture from my friend.
The Tiger 131 of the Tank Museum Bovington, an umbrella was installed on the cupola. I heard that two poles are inserted to the short tubes at the edge of cupola's hatch.
In November 1942, an umbrella equipment Regenschirm introduced on the Tiger I cupola. See a reference information. Several pictures in War time are found in some books and web.
Other reference photos
Source: Bundesarchiv_Bild_101I-458-0077-12, Russland, Panzer_VI (Tiger_I)_mit_Kettenschaden
(2) Source: web
(3) from friend.