Can we add new file extensions to the project collaboration tab advanced search options?
1 - Go to Administration / Lookups
2 - Filter by 'Search File Types' / Lookup ID: SEARCH_FILE_TYPE
3 - Access to it and click on 'Values'
4 - Click on 'New' button
5 - Lookup Name put something like 'MS Excel XLSX' and ID: xlsx
6 - Save & Return
7 - Now the item it's available and filter works as expected
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