SUMMARY

    It is not obvious which filter tabs displayed in a Dolphin
    search are active. It may be that they are not even recognised
    as providing choices.

    When clicking on the "search" icon or pressing Ctrl-F, Dolphin
    provides a search input box. Under this there are options for
    "Filename", "Content", "From Here" and "Your Files".

    When searching for, for example, a tag (by typing tag:mytag in
    the search box) you may get no results as you have the
    "Filename" filter selected. If you switch to "Content" you then
     see the results.

STEPS TO REPRODUCE:

    Using the example of searching for a tag, create a "File" under
    Documents and give it a tag "mytag". Make sure baloo is seeing
    it with "baloosearch tags:mytag"

    Do the same search in Dolphin, Ctrl-F to open a search box and
    type "tags:mytag"

OBSERVED RESULTS

    You may get no results/an empty panel

    You need to press the 'Content' button to reveal the results.

EXPECTED RESULTS

    Sufficient visual hints to recognise the "Filename" and "Content"
    (and indeed the "From Here" and "Your Files") are filters, that
    you can recognise which are selected and that you can click on
    them to change options

SOFTWARE/OS VERSIONS

    Neon Testing
    Dolphin : 20.12.0
    Plasma : 5.20.4
    Frameworks : 5.78.0
    Qt : 5.15.2

ADDITIONAL INFORMATION

    If you don't know, it's not clear that "Filename" and "Content"
    are buttons. Even if you do, it's not necessarily clear whether a
    "darker" background denotes the button is pressed or it is
    "not selected" tab (as a tab might be presented in a browser)

    A possible way of making it clearer is presenting the options as
    if they were browser tabs