Summary

Certain special characters inside MS office attachment such as Word (both .doc or .docx) and Excel (.xls) are not displaying properly when viewed in the new File Preview macro (newly introduced in 5.7.x)

Steps to Reproduce

Steps to reproduce:

1. Create a MS Office file containing special characters:
   • Umlaut characters like "ß" . Example file german-umlauts.xls is attached
   • Polish characters like "ą". Example file polish-characters.docx is attached
   • Cyrillic characters. Example file testcyrillic.doc is attached
   • Arabic characters. Example file العَرَبِية‎.docx
     
2. Create a page
3. Edit the page, Insert > File & Image > insert the file > save page
4. Preview the Excel file. The special characters will be garbled:
   

or

1. Add a page, insert the macro Attachments
2. Add the sample attachments to the page
3. Save the page, click on "Preview"
   
4. The special characters are garbled

Expected Results

All characters are displayed correctly

Actual Results

Some characters are garbled and not displayed properly

Notes

This issue is not reproducible in

1. PDF file
2. While clicking "View" in the attachment macro (Using the Office Viewer instead of View File Macro)

Characters observed to be causing this issue:

1. Umlaut characters like "ß" .
2. Polish characters like "ą"
3. All Cyrillic characters
4. All Arabic characters