smacdonald2008 this is probably one of the worst upgrades I have had to deal with with regards to SP's...
I am seeing the same issue reported here, and it is only happening if you install SP2 (126.96.36.199) and THEN install SP3 (188.8.131.52) If you install SP3 on a base AEM instance (184.108.40.206) then editing dialogs works fine.
The error is very clear, the file `/libs/cq/gui/components/siteadmin/admin/properties/FilteringResourceWrapper.jsp` is not in the repository. If I copy the file from a clean AEM 6.3 SP2 instance into my SP3 instance, I can edit dialogs in my SP3 instance.
This suggests to me that proper testing of the scenario described above was not tested before SP3 release (install SP2 -> install SP3). Might be an honest mistake, but I'd love to know if there is a path forward?
I am also having the same issue and not able to edit any of my components after installing 6.4.3. The previous AEM version was 6.4.2. When I checked the log file I found a SlingExecption
org.apache.sling.scripting.jsp.jasper.JasperException: /libs/cq/gui/components/authoring/dialog/dialog.jsp(39,2) File "/libs/cq/gui/components/siteadmin/admin/properties/FilteringResourceWrapper.jsp" not found