That's usually there if you don't have a valid licence. On local development I would suggest checking you have a licence file and it hasn't been deleted. Also try recreating the licence file and make sure you have the right version selected
Also be aware that there was some licencing change with server bound licences as documented here https://world.episerver.com/blogs/filip-gondek/dates/2017/11/new-license-model-2018/
I have checked license file and it was not deleted. Also, i have generated a new license file but still seeing same message "NOT FOR COMMERCIAL USE". Same license file is working for old CMS version code
As I recall it "NOT FOR COMMERCIAL USE" is added to all page titles when the license is a development license and in that case it is intentional.
If there was something in 7.5 that caused this to not show up i don't know.
Yes, I think Erik is right that will appear in Dev licences as it's appearing on my current project which is running our partner developer licence.
I have observed that after CMS upgrade from 7.5 to 10.8, i am seeing " NOT FOR COMMERCIAL USE" text is displaying for each page title and this string is appending in last with page title name. What could be reason for this?