ERC777: Clarify ERC20 transfer for contracts

EIPS/eip-777.md

@@ -1086,15 +1086,21 @@ when sending, minting and transferring token via [ERC777] and [ERC20]:
       <code>ERC777TokensRecipient</code><br/>not registered
     </td>
     <td>regular address</td>
-    <td align="center">continue</td>
-    <td rowspan="2" align="center">continue</td>
+    <td colspan="2" align="center">continue</td>
   </tr>
   <tr>
     <td>contract</td>
     <td align="center">MUST <code>revert</code></td>
+    <td align="center">SHOULD continue<sup><a id="continue-footnote-backlink" href="#continue-footnote">1</a></sup></td>
   </tr>
 </table>
 
+> <a href="#continue-footnote-backlink"><small id="continue-footnote">1.</small></a>
+> <small>The transaction SHOULD continue for clarity as ERC20 is not aware of hooks.</small>  
+> <small>However, this can result in accidentally locked tokens.</small>
+> <small>If avoiding accidentally locked tokens is paramount, the transaction MAY <code>revert</code>.</small>
+
+
 There is no particular action to take if `tokensToSend` is not implemented.
 The transfer MUST proceed and only be canceled if another condition is not respected
 such as lack of funds or a `revert` in `tokensReceived` (if present).