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stdlib/REPL/src/LineEdit.jl

@@ -458,13 +458,15 @@ prompt_string(f::Function) = Base.invokelatest(f)
 
 function maybe_show_hint(s::PromptState)
     isa(s.hint, String) || return nothing
+    # The hint being "" then nothing is used to first clear a previous hint, then skip printing the hint
+    # the clear line cannot be printed each time because it breaks column movement
     if isempty(s.hint)
-        print(terminal(s), "\e[0K")
+        print(terminal(s), "\e[0K") # clear remainder of line which had a hint
         s.hint = nothing
     else
         Base.printstyled(terminal(s), s.hint, color=:light_black)
         cmove_left(terminal(s), textwidth(s.hint))
-        s.hint = "" # clear line remainder of line but only once after a hint to allow column movement
+        s.hint = "" # being "" signals to do one clear line remainder to clear the hint next time if still empty
     end
     return nothing
 end