Possible WordPress .htaccess file contains suffix name?

Solution:

htaccess file with suffix name like -1516661360 is backup of your real .htaccess file. It backuped from server side. You can see, when backup was done, if will convert 1516661360 UNIX epoch time to date.

If you’ll go to Dashboard -> Settings -> Permalinks and click Save changes, then wordpress will create new .htaccess file for your permalinks structure, if it not exists.