Morph search functions as per L4 i.e. surface by default and needing lemma: prefix for lemmas.
g:word doesn't offer as many suggestions as L4 e.g. g:log, g:logi
I have filed a case for both issues you mentioned (the Search Helps, and the suggestive dropdown disparity between L4 and L5). Thank you.
We've updated the Search Cookbook helps in the next alpha to reflect the "surface by default" behavior.
