(Windows) Renaming page causes duplication in index

--- When renaming a page and changing only the case of one or more letters, a duplicate is created in the left hand side index (one page with the original name, and another with the new name).

--- Clicking on either of the duplicates in the index opens the same page, although it remembers a unique 'last cursor position' for each one.

--- There is only one physical file with the new name in the ~notebooks directory.

--- Renaming again by adding or changing a letter fixes the issue (duplicate disappears)... So the current workaround for changing just the case in the page name is to rename twice, first adding a letter, then removing the letter and changing the case.

To recreate issue:

1) Create a new page with the name "test"
2) Right click on the page in the index and choose 'Rename Page'
3) Rename the page to "Test"
4) Duplication should be seen in the index
5) Note that duplication remains after closing and opening Zim.
6) Rename either page again, changing or adding a letter
7) Duplication goes away