When you just want to submit a form, use:

# Submits the page, without specifying a button to click. Actually, no
+ button is clicked at all.
# This used to be a synonym for $mech->click("submit"), but is no long
+er so.

$mech->submit()
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If you want to click a button that isn't named, try to use the

$mech->click_button( ... )
# number => n
#Clicks the nth button in the current form. Numbering starts at 1.

# value => value
# Clicks the button with the value value in the current form.
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