Hi Thomas,
Thank you for contacting Syncfusion support.
On analyzing from the provided information, we suspect that the mentioned with “SfRichTextEditor not focusing properly in UWP platform” would be due to Xamarin forms version. If the Xamarin Forms version is above 4.3, to resolve the issue we suggest you to set the Target version as “version 19.0.3 (10.0; Build 18362)” in UWP project. We have prepared a sample based on the provided information, which can be downloaded from the below link.
If the issue still persists, in the provided sample from your side, kindly provide us the more information about the issue scenario, such as the focus is getting lost if any other actions takes place in the toolbar or after any customization action is performed out of the editor (any UI actions such as buttons at design level), which will be helpful for us to provide a prompt solution at earliest.
Regards,
Devaraj S