It's sad that Notion and Whatsapp dont have desktop apps like linux. I use them a lot and having separate apps for them is definitely a plus.

There are workarounds which package these apps and make em work on Linux, but then updating them is a headache.

When trying to find a solution, luckily I came across this answer which solved all of my problems.

Steps

1. Make sure you have a chromium based browser
2. Go ahead and make a desktop file 2.1 vim ~/.local/share/applications/whatsapp.desktop
3. Copy and paste the configuration below

#!/usr/bin/env xdg-open
[Desktop Entry]
Name=WhatsApp
GenericName=WhatsApp
Comment=WhatsApp desktop webapp
Exec=/usr/bin/google-chrome-stable --app=https://web.whatsapp.com/
Terminal=false
Type=Application
StartupNotify=true
MimeType=text/plain;
Categories=Network;Application;
Keywords=WhatsApp;webapp;
X-Ubuntu-Gettext-Domain=WhatsApp
StartupWMClass=web.whatsapp.com

1. Just make sure the Exec section has the chromium based browser you use. For vivaldi it was /usr/bin/vivaldi-stable for me. To find the path, just type which chrome in your terminal.
2. Save it and that's it! Just

Here's the Notion desktop file I use

#!/usr/bin/env xdg-open
[Desktop Entry]
Name=Notion
GenericName=Notion
Comment=Notion desktop webapp
Exec=/usr/bin/vivaldi-stable --app=https://www.notion.so
Terminal=false
Type=Application
StartupNotify=true
MimeType=text/plain;
Categories=Network;Application;
Keywords=Notion;webapp;
X-Ubuntu-Gettext-Domain=WhatsApp
StartupWMClass=notion.so