Unable to view/Change Desktop Background Wallpaper Freezes

[nairra]

I was stuck with a problem with Linux Mint 20.2 since long where I was unable to view/change the wallpaper on my HP Elitebook 8470p . I could not find any relevant post in the forum, hence posting for the benefit of others.
Issue:
Unable to Change/View Desktop Background, not able to view wallpapers
Right click on the desktop screen and opening the Change Desktop Background would result in freezing the window and I was unable to view any wallpapers. But system can be used for other purposes.
Solution:
-Right click on the desktop and open Terminal
-Using same user without sudo/root, type cinnammon-setttings (This would throw error.) In my case found that there was a permission denied for file /usr/local/lib/netscape/mime.types which had access permission only for root
-Changed permission of file /usr/local/lib/netscape/mime.types to 755 and retried executing cinnamon-settings and issue was resolved.

Find below the Terminal output for reference:
test@/usr/share >cinnamon-settings
Using PAM module (python3-pam)
Loading Backgrounds module
Exception ignored in thread started by: <bound method ThreadedIconView._do_load of <cs_backgrounds.ThreadedIconView object at 0x7ff058f213c0 (cs_backgrounds+ThreadedIconView at 0x1834d70)>>
Traceback (most recent call last):
File "/usr/share/cinnamon/cinnamon-settings/modules/cs_backgrounds.py", line 764, in _do_load
pix = PIX_CACHE.get_pix(filename, BACKGROUND_ICONS_SIZE)
File "/usr/share/cinnamon/cinnamon-settings/modules/cs_backgrounds.py", line 573, in get_pix
mimetype = mimetypes.guess_type(filename)[0]
File "/usr/lib/python3.8/mimetypes.py", line 291, in guess_type
init()
File "/usr/lib/python3.8/mimetypes.py", line 364, in init
db.read(file)
File "/usr/lib/python3.8/mimetypes.py", line 205, in read
with open(filename, encoding='utf-8') as fp:
PermissionError: [Errno 13] Permission denied: '/usr/local/lib/netscape/mime.types'

test@/usr/share >ls -tl /usr/local/lib/netscape/mime.types
-rw------- 1 root root 106 Dec 20 2020 /usr/local/lib/netscape/mime.types
test@/usr/share >sudo chmod 755 /usr/local/lib/netscape/mime.types