Opening some legacy code in Notepad++ and notice a few occurrences of FF character below function comment headers. They are ASCII code 12 which is the Form Feed character. Are FF characters valid in MISRA C2 standard please? Apologies I don't have access to PC-Lint/QAC checker.
You appear to be talking about a commercial product, whose announcements give no useful information, e.g., this press release.
Form feed is stated explicitly to be part of the character set in ISO/IEC 9899:199 (E) 5.2.1 Character sets. If the tool advised you not to use a documented, standard feature, that would be a defect in the tool itself. A comparable issue would be whether to allow tab characters in leading whitespace on a line.
Given that context, the use of form feed characters is a stylistic issue unrelated to static analysis, and I would not expect the two to be confused in a commercial product.