When using an annotation tool or edit tool the Format panel will be opened by default on the right side. But once you close the panel, the option will be recorded by the software, and next time you use an annotation/edit tool, the Format panel is not opened. Please follow below to bring it up.
If you're running on Windows OS, please select a comment tool and click on the area where you would like to add an annotation, then click on the following highlighted area to expand the Format panel.
The above instruction is applicable for Foxit PDF Editor/Reader for windows desktop V11.0 and greater.
If you're running on Mac OS, please do the following to show/hide the format panel:
For Foxit PDF Editor/Reader for MAC V11.1 and greater, please click on the following highlighted area to expand the Format panel.
For Foxit PDF Editor/Reader for MAC V11.0,please click the button at the bottom right corner to show/hide the Format panel.