Lychi considers the structures above as tautomers (same hash key) with -keto-enol option off, however the number of hydrogens is not the same so they should be perhaps get different hash keys.
Hi Oleg, this is an example of what the InChI technical document considers as "hard" deprotonation (pages 35-6 under section "Normalization Limits"). Likewise, see the methazomalide example in this paper.
Hi Trung
In the example below
Lychi considers the structures above as tautomers (same hash key) with -keto-enol option off, however the number of hydrogens is not the same so they should be perhaps get different hash keys.