The progress of fixing the bug will be posted in this blog so visited me frequently if you are interested in it.
WTP - Bug 243799
Steps to Reproduce
1. Have 2 xsd files, TestSchema1.xsd and TestSchema2.xsd, where
TestSchema2.xsd includes TestSchema1.xsd.
2. Open both xsd files in Eclipse.
3. Verify that both xsd files validate properly.
4. Add a new type to TestSchema1.xsd and validate the updated schema.
5. Switch back to TestSchema2.xsd and attempt to use content assist to user
the new type added in step 4.
6. Regardless of whether content assist is triggered automatically (e.g. add a
new element or attribute and then enter the type parameter leading content
assist to pop-up with the available types) or manually (via ctrl-space inside
the quotes of the type parameter), the new type entered in step 4 is not
visibile for content assist.
7. If you manually enter the new type from step 4 however, the validation is
successful. However, even after this content assist still doesn't make the new
type visible.
8. If TestSchema2.xsd is closed and then re-opened in Eclipse, content assist
now properly sees the the new type.
9. Directly related, if you instead remove a type from TestSchema1.xsd in step
4, then the TestSchema2.xsd editor's content assist continues to show the
removed type even though it is no longer visible and validation fails.