Today my customer called me up and told that Notes which are getting created in Dynamics 365 are showing up in the portals with HTML tags and stuff and the look and feel is completely distorted.
For me it was surprising because till last night everything was just working fine. So obviously something might have changed other than this.
After searching for couple of hours I found this link from Microsoft Docs – https://docs.microsoft.com/en-us/powerapps/maker/portals/known-issues.
It clearly states that rich text features of Notes are not supported in PowerApps portals as of the time of writing this blog. Check for the first point in the list under General Issues section.
And last night my customer enabled the rich text feature of notes. In case you are not aware of the rich text feature introduced in notes, check this out.
Hope this helps!