Spreadsheet: bold format not applied

Using Spreadsheet 3.1.2, the bold style is not applied when clicking the “B” decoration button. Italic and underline do work though. Bug?

Thanks,
Yuerg

Could you please, clarify the details of the problem, as the bold style applies well for me here:
https://docs.dhtmlx.com/spreadsheet/samples/01_init/01_basic.html
Using browser, spreadsheet config details or the exct steps to reproduce the problem, would help a lot.