Odd behavior with tkinter frames

import tkinter as tk

class GridButtonsBase(tk.Frame):
    def __init__(self, parent=None, **kwargs):
        super().__init__(parent)
        self.reset_containers()
        self.draw()
        tk.Button(self, command=self.mutate_borders).grid(row=1, column=1, padx=10, pady=10, sticky='news')

    def reset_containers(self):
        self.borders = []
        for _ in range(3 * 3):
            self.borders.append(tk.Frame(self))
        self.border_map:list[list[int, int, int, int]] = [] #row, col, columnspan, rowspan

    def draw(self):
        self.border_map = [[0, 0, 3, 1], [1, 0, 3, 1], [2, 0, 3, 1], [0, 0, 1, 3], [0, 1, 1, 3], [0, 2, 1, 3]]
        for row in range(3):
            self.rowconfigure(row, minsize=100)
        for col in range(3):
            self.columnconfigure(col, minsize=100)
        self.draw_borders()

    def draw_borders(self):
        for index, entry in enumerate(self.border_map):
            if entry is None: continue
            row, col, colspan, rowspan = entry
            self.borders[index] = tk.Frame(self, bg='green')
            self.borders[index].grid(row=row, column=col, rowspan=rowspan, columnspan=colspan, padx=3, pady=3, sticky='news')

    def mutate_borders(self):
        self.mutate_border_map()
        for border in self.borders:
            border.grid_forget()
        for index, entry in enumerate(self.border_map):
            row, col, colspan, rowspan = entry
            self.borders[index].config(bg='red')
            self.borders[index].grid(row=row, column=col, rowspan=rowspan, columnspan=colspan, padx=3, pady=3, sticky='news')
            print(f'frame info: pos: ({self.borders[index].grid_info()["row"]}, {self.borders[index].grid_info()["column"]}); rowspan: {self.borders[index].grid_info()["rowspan"]}, columnspan: {self.borders[index].grid_info()["columnspan"]}')

    def mutate_border_map(self):
        cluttered_border_map = [[0, 0, 3, 1], [1, 0, 3, 1], [2, 0, 1, 1], [2, 1, 2, 1],[0, 0, 1, 2], [2, 0, 1, 1], [0, 1, 1, 3], [0, 2, 1, 3]]
        if True: # change to false to change behavior
            self.border_map = []
            for elem in cluttered_border_map:
                if elem not in self.border_map:
                    self.border_map.append(elem)
        else:
            self.border_map = cluttered_border_map
        print(self.border_map)

    def clear_view(self):
        for border in self.borders:
            if border is None: continue
            border.grid_forget()

class Temp(tk.Frame):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.parent = parent
        self.gb_config: GridButtonsBase = GridButtonsBase(self)
        self.gb_config.pack()


root = tk.Tk()
Temp(parent=root).pack()
root.mainloop()