Description:
Saving a calc document in native LibreOffice format with a formula using a blank between function name and initial parentheses may lead to a file which may not be successfully opened by Excel.

This is very similar to the problem 104186 I reported earlier (and which was fixed afterwards). LO seems to violate paragraph 5.14 (titled "Whitespace") of the document "OASIS Open Document Format for Office Applications (OpenDocument) Version 1.2" which clearly states:

"whitespace shall not separate a function name from its initial opening parentheses."

If I manually remove the invalid blank from the LO save, Excel can open the saved LO file successfully.

Steps to Reproduce:
1. Create a blank document with LO calc sheet with LO 6.2.2.2, using German localisation
2. Use in the document the parameterized function JAHR (German for YEAR), and use a cell reference as parameter for JAHR. In the formula, add a space character between the function name and the initial brace. 
3. Save the document in default LO format (.ods)
4. Open the document with a German version of Microsoft Excel 2016.
5. Excel reports an error for the cell with the JAHR function
6. Repeat steps 1 to 5, but do not add an additional blank. Result: Excel opens the file successfully.

Actual Results:
Error message in Excel when opening the LO file

Expected Results:
No error message by Excel when opening the LO file


Reproducible: Always


User Profile Reset: No



Additional Info:
The application must not save any whitespace between a function name and the initial opening parentheses. In my understanding this violates ISO/IEC 26300-1:2015.

See also bug 103186 where the same issue was resolved for saves in ECMA-376 (Excel) format, which has the same constraints concerning illegal space characters between function name and initial brace.