: PGP keys need importing:
-> 1C61A2656FB57B7E4DE0F4C1FC918B335044912E, required by: dropbox
:: Importing keys with gpg...
gpg: WARNING: unsafe permissions on homedir '/home/limo/.gnupg'
gpg: key FC918B335044912E: no user ID
gpg: Total number processed: 1
problem importing keys
[limo@lenovo ~]$
Why me!!! 
Even try this one in terminal?
gpg --keyserver hkp://pgp.mit.edu --recv-keys FC918B335044912E
I just tried this keyserver and worked for me.
Nice, this one doesn’t work for me
[lain@wired ~]$ gpg --keyserver hkp://pgp.mit.edu --recv-keys FC918B335044912E
gpg: keyserver receive failed: No keyserver available
What about manual import
wget https://linux.dropbox.com/fedora/rpm-public-key.asc
gpg --import rpm-public-key.asc
I got below.
[p@arch ~]$ gpg --keyserver hkp://pgp.mit.edu --recv-keys FC918B335044912E
gpg: key FC918B335044912E: “Dropbox Automatic Signing Key linux@dropbox.com” not changed
gpg: Total number processed: 1
gpg: unchanged: 1
[limo@lenovo ~]$ gpg --keyserver hkp://pgp.mit.edu --recv-keys FC918B335044912E
gpg: WARNING: unsafe permissions on homedir '/home/limo/.gnupg'
gpg: keyserver receive failed: No data
[limo@lenovo ~]$
No data
Maybe their server is down! Try later perhaps?
Try the manual way once
How to do it?
Run these commands
wget https://linux.dropbox.com/fedora/rpm-public-key.asc
gpg --import rpm-public-key.asc
[limo@lenovo ~]$ wget https://linux.dropbox.com/fedora/rpm-public-key.asc
--2021-09-17 14:07:37-- https://linux.dropbox.com/fedora/rpm-public-key.asc
SSL_INIT
Loaded CA certificate '/etc/ssl/certs/ca-certificates.crt'
Resolving linux.dropbox.com (linux.dropbox.com)... 216.137.37.7, 216.137.37.118, 216.137.37.126, ...
Connecting to linux.dropbox.com (linux.dropbox.com)|216.137.37.7|:443... connected.
still waiting!
It should have taken 1-2 seconds at most
CTL C
then again did it, I had
wget https://linux.dropbox.com/fedora/rpm-public-key.asc
--2021-09-17 14:11:54-- https://linux.dropbox.com/fedora/rpm-public-key.asc
SSL_INIT
Loaded CA certificate '/etc/ssl/certs/ca-certificates.crt'
Resolving linux.dropbox.com (linux.dropbox.com)... 216.137.37.7, 216.137.37.12, 216.137.37.126, ...
Connecting to linux.dropbox.com (linux.dropbox.com)|216.137.37.7|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 975 [application/octet-stream]
Saving to: ‘rpm-public-key.asc’
rpm-public-key.asc 100%[==================================>] 975 --.-KB/s in 0s
2021-09-17 14:11:55 (6.91 MB/s) - ‘rpm-public-key.asc’ saved [975/975]
[limo@lenovo ~]$
ok now import it with this command
gpg --import rpm-public-key.asc
Seems we are almost there! I hope.
[limo@lenovo ~]$ gpg --import rpm-public-key.asc
gpg: WARNING: unsafe permissions on homedir '/home/limo/.gnupg'
gpg: key FC918B335044912E: public key "Dropbox Automatic Signing Key <linux@dropbox.com>" imported
gpg: Total number processed: 1
gpg: imported: 1
[limo@lenovo ~]$
Looks like a success to me!
Now, finally try installing dropbox
yay -S dropbox --noconfirm
WOW!
Finally appeared in my menu!
Thanks a lot flyingcakes and thanks a lot QAP
This forum and you guys are amazing! 
nice got there in end! welcome to forum and spread the word!
Just curious, does installing from yay compile from source? I read the messages while installing Dropbox and catfish, seemed to me it was compiling something on my machine.
I hope you brief answer and guide me to read more! Please.
Thank you.
Yes but you can use just binaries instead where already compiled and for faster install.
i.e. notice how more votes and can choose brave-bin instead of brave below as example.
Find the software you want and install using pacman command from Official Repo
If not there then yay command to install from Unofficial Arch User Repo . Look at votes, comments and package not out of date first.
But forum will always help best they can if create separate thread. Lots of reading from Arch wiki and Distrotube is great youtube channel for knowledge! 