This simple library shows the current recursion level in the mode-line.
For example if you enable-recursive-minibuffers and enter
M-x recursive-edit M-x recursive-edit M-x M-x M-x, the modeline
indicator will show [↲↲↲⟲⟲]. This indicator is an alternative to the
brackets, Emacs shows by default around the modes, and to the counter
shown if minibuffer-depth-indicate-mode is activated.
If you are using recursion-indicator you might want to remove %[ and
%] from mode-line-modes and disable
minibuffer-depth-indicate-mode.
(use-package recursion-indicator
:demand t
:config
(recursion-indicator-mode))