I also had a case for this opened in May 2020 where I directly referenced this Idea Exchange submission, and will copy details relevant comments from my case log.

In sum, I think this was a defect that was fixed in August 2022 and will reiterate my last comment that I believe anyone still seeing this should open a case.

CDI - Different term highlighting in record display does not match query, in comparison to PCI where highlighting is complete including stop words
* 05310266

Analyst advised: "In case of an exact match, the title highlight should include also the stop words. This, as you mentioned, is a good way to let the user know easily they hit the right result. If the match isn't exact, the stop words shouldn't be highlighted, again in order to allow the user a quick initial navigation among the brief results. But there are are few variations to this - namely, what counts as "exact match". For example, the search for "Playing the game; is sport as good for race relations as we'd like to think" - will get the full highlight. But it can be flexible - if you change some of the words in the query to their plural/singular forms ('races', 'sports', or 'relation') you will still see the full highlight. However, CDI isn't expanding 'we' when the indexed term is 'we'd'. Development team verified that this is the expected behavior for CDI, and that in fact it was the same for PCI (which is why 'we' wasn't highlighted then). So, the basic behavior is the same." 28.4.2021 SvG

Responded to query only item outstanding re the Idea Exchange submission included in the original case for random stop word highlighting. 29.4.2021 SvG

Analyst advised: "Currently, there's a fix planned for both for CDI and Primo side, to prevent the highlight of stop words when they appear separately, in addition to the expected highlight of them as part of an exact match. For example, a search for "lord of the rings" will highlight, as expected, the full exact match, but also the words "off" or "the" before or after the full highlight.", and also seemed to not see the issue in the Idea Exchange entry. 29.4.2021 SvG

Responded to point analyst to screenshot on the entry, which shows the issue. 30.4.2021 SvG

Analyst confirmed screenshot missed, and that it seemed an issue with the separate stop words as per the planned fix and not the "exact match" highlight. 25.2.2021 SvG

Analyst advised tentatively planned fix for May 2022, which is extended as the fix must include also changes to the search mechanism. 15.6.2021 SvG

Analyst advised fix estimation pushed back to August 2022. 20.2.2022 SvG

Analyst advised firm fix in August 2022 Release. 8.7.2022 SvG

Update of fix in the August 2022 Release and case set to closing. 22.8.2022 SvG

Responded to advise cannot confirm and added a screenshot per the described fix in April 2021 showing the same additional highlighting. 22.8.2022 SvG

Analyst is querying with PM re: "stop words detached from the query itself are no longer highlighted, but the adjacent stop words are. " 22.8.2022 SvG

Added comment referencing earlier updates by analyst and the desire to ensure both aspects are resolved: "to prevent the highlight of stop words when they appear separately, in addition to the expected highlight of them as part of an exact match. For example, a search for "lord of the rings" will highlight, as expected, the full exact match, but also the words "off" or "the" before or after the full highlight." 24.8.2022 SvG

Analyst advised: "What was actually fixed in this case is that only the words in the search phrase will be highlighted, not only the 'exact match'. For example, when searching 'lord of the rings', these words will be highlighted for all phrases that contain these words adjacent to each other. Indeed, according to the release notes, previously, the text 'of the' was highlighted even though it did not begin with Lord and/or end in Rings and currently, 'of the' is highlighted only when it appears in adjecent to the search phrase." 8.9.2022 SvG

I still cannot replicate this. I'll attach images of what I see for one of the last examples Lacey posted with custom code stripped out to clearly show no stop word underlining.
I suggest this be opened as a case for anyone seeing it, so there can be explanation provided for what appears to be an intermittent defect.

Another example: look at all the times "and" is highlighted in the search results here: https://mnpals-ndc.primo.exlibrisgroup.com/discovery/search?query=any,contains,kingdom%20of%20time%20and%20love%20is%20now&tab=SlotTab&search_scope=MyInst_and_CI&vid=01MNPALS_NDC:NDC&facet=tlevel,include,online_resources&offset=0&pcAvailability=false

In the comments folks have asked for proof of this highlighting of stop words still happening in PrimoVE, which makes sense if not everyone is seeing this behavior.

I used one of the URLs posted in a previous comment by Manu where they say they don't see this problem. When I go to the URL Manu provided, I do see this problem still appearing. It just may have been less noticeable given the very low color contrast of the highlighting color in this institution's view customization. I have circled the many instances of highlighted/underlined lone appearances of stop words in the text including "to," "the,' and "of" in the attached image.

What is especially problematic is that these are not times when the stop word precedes or follows a keyword. They are times when the stop words are not adjacent to the keywords AT ALL.

This is the URL I used: https://basel.swisscovery.org/discovery/search?query=any,contains,party%20of%20god%20uses%20media%20and%20resources%20to%20succeed%20in%20the%2021st%20century&tab=41SLSP_DN_CI&search_scope=DN_and_CI&vid=41SLSP_UBS:live&lang=en&offset=0

It still is happening for our searches; note "The" being underlined even when it was not part of the original search query.

https://mnpals-ndc.primo.exlibrisgroup.com/discovery/search?query=any,contains,peloponnesian%20war&tab=SlotTab&search_scope=MyInst_and_CI&vid=01MNPALS_NDC:NDC&offset=0

Can this be closed so the votes can be given back?

Has this been fixed in the meantime? As Stacey in 2020, I do not see the same problem (Primo VE).

https://basel.swisscovery.org/discovery/search?query=any,contains,party%20of%20god%20uses%20media%20and%20resources%20to%20succeed%20in%20the%2021st%20century&tab=41SLSP_DN_CI&search_scope=DN_and_CI&vid=41SLSP_UBS:live&lang=en&offset=0

If somebody still sees this happening, post a link?

Oh, this would be fabulous.

The highlighting of stop words happens even when the stop words are not part of the original query itself. This is the same thing to us. When searching "new york times". Primo highlights every single "the" in the search results. There are so many "the" in there.

Agreed.

Agree - it is just visual disturbance

I'm not seeing 'the' highlighted in my Primo, Lacey.
Can you provide a link to your environment?

The highlighting of stop words happens even when the stop words are not part of the original query itself. For example, searches for "peloponnesian war" results in highlights for the word "the" in the search results.

Any update on this?