How to fix not being able to copy and paste into the web version of Outlook

In Google Chrome

Click the three vertical dots in the top right hand corner.
Select "Settings" from the drop down menu.
A new tab will open. Navigate to the "Privacy and security" tab on the left hand side and click "Site settings"
Click "View sit permissions and data stored across sites".
Search Outlook in the top right hand corner. You will see an entry for office.com. Click on the arrow next to it.
Select the arrow next to outlook.office.com.
Scroll down to "Clipboard" and select "Allow" from the drop down menu on the right hand side.
Completely close Chrome and reopen it and you should now be able to copy and paste within Outlook.