Inserting a tab character that would put us at the right edge of the buffer inserts two tabs (one to get us to the right edge of the buffer, one more after we wrap)

#include <windows.h>
int main() {
        CONSOLE_SCREEN_BUFFER_INFOEX csbiex{};
        csbiex.cbSize = sizeof(csbiex);
        GetConsoleScreenBufferInfoEx(GetStdHandle(STD_OUTPUT_HANDLE), &csbiex);
        SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), COORD{(SHORT)(csbiex.dwSize.X - 9), csbiex.dwCursorPosition.Y});
        WriteConsoleW(GetStdHandle(STD_OUTPUT_HANDLE), L"|\t|\n", 4, nullptr, nullptr);
        return 0;
}

Inserting a printable control character at the right edge of the screen (ala ^A) when only the ^ would fit emits a ^ and a space.

Inserting a printable control character (^D) at the right edge of the screen when both ^ and D fit and then backspacing it deletes the ^, not the D: