The merge queue at the bottom of entity pages always shows this help text:
Please navigate to the pages of other entities you wish to merge and select the "merge" link.
There is an alternative text that is supposed to be displayed when there are at least two entries, i.e. a merge is possible:
When you are ready to merge these, just click the Merge button. You may still add more to this merge queue by simply browsing to the entities page and following the merge link.
Due to two typos in the test (merge.reday_to_merge instead of merger.ready_to_merge), this other text is never visible to the user.