…which produced random results

I could only find instances that were below the cursor,

It doesn’t sound like you achieved “random results”.
It seems like Notepad++ did what it was told to do, predictably and consistently.

Report an issue or make a feature request here: https://github.com/notepad-plus-plus/notepad-plus-plus/issues/

Hey that worked perfectly, thanks. The name of the options is not very serious… a gray label with a warning instead of the explanation between parentheses would be more adequate. Is there some place where I can make suggestions for the GUI, to make it more professional and less… amateur? Thanks.

Well, that case is discussed by @guy038 in the earlier posting I referenced; following the logic presented there indicates that your example will indeed not be matched.

However, there is a way to get your desired behavior. In Settings (menu) -> Preferences -> Delimiter, change the “Word character list” as shown here: http://imgur.com/a/FhKc1

Textually, change the radio button so that “Add your character…” is selected, and add the $ to the text box below it.

I’m afraid it doesn’t. Kindly search for $abc using the Entire Word option with these:

bla $abc(
bla $abc)
bla $abc[
bla $abc{
bla {$abc} 404_NOT_FOUND
bla ($abc 404_NOT_FOUND
bla )$abc 404_NOT_FOUND
bla [$abc 404_NOT_FOUND
bla ]$abc 404_NOT_FOUND

As you can see, anything with a (, ), [, ], {, } before it won’t be found by Notepad++ 7.3.3 for Windows (X86).

This makes the Entire Word option so untrustworthy that I can never use it, not with PHP at least.

“whole word” IS practical.

A “whole word” is not strictly defined as “that which is surrounded by spaces”.

If any of (, ), [, ], {, } is next to what looks like a word, it IS still found when doing a search with “whole word” option enabled, for example, all 12 of the following lines will be found when searched for “abc”:

abc(
abc)
abc[
abc]
abc{
abc}
(abc
)abc
[abc
]abc
{abc
}abc

But…perhaps I am misunderstanding what is meant by some of your statements…

A pretty good discussion of what makes up a “word” and how the search engine deals with it was done by @guy038 here: https://notepad-plus-plus.org/community/topic/13004/bugs-in-normal-search-for-v7-2-2-on-windows-7

http://npppythonscript.sourceforge.net/download.shtml

Occasionally I leave the “In selection” tick box on the replace window ticked, then I get very confused about why a replace does not do what I want. Unticking the “In selection” box and shouting at my mouse for clicking the wrong things lets the replacement work OK.

Must be something specific with your installation or usage.
Could you make a screenshot and upload it. E.g imgur (no registration needed)
It should show the find dialog reporting the can’t find text message
together with the text with should be searched.

Cheers
Claudia