Appending identical text to the end of every line in a list is the mirror image of prefixing, and it comes up just as often — usually when a list of values needs a shared ending before another system will accept it.
Typical shapes
A list of page paths that all need /index.html appended. A set of keywords that all need the same qualifier attached. A column of identifiers that need a file extension before a bulk upload will recognise them.
Consistency is the point
Doing this by hand across a few hundred lines will produce at least one line with a typo or a missing character, and that line will be the one that breaks the import. A single-pass rule cannot make that mistake.
Order matters when combining
If a list needs both a prefix and a suffix, apply them as two clean passes rather than trying to reconstruct each line manually. Each pass is verifiable on its own.
Try it: Add Suffix on SeoWolf's Notepad.