Mike,
If I'm understanding your question correctly, the short answer is that combined text fields are by nature Multi-Select Text fields, though they are static. To make them editable, you need to use an automation to copy those values into another (non-formula) Multi-Select Text field.
A more complex answer, which may or may not speak directly to your challenge, I discovered just yesterday. I found the help documentation on Formula - Multi-Select Text fields to be helpful, particularly the section about combining checkboxes.
https://help.quickbase.com/user-assistance/formula-multi-select-text.htmlMy situation was similar to yours, except I had nested Combined Text fields (summary field of summary fields) that I wanted to convert to a single editable Multi-Select Text field. I used the following formula in a Formula Multi - Select Text field to convert the nested combined text field into a static Multi-Select Text field, using as many Part functions as I anticipated options being selected (or more, the result is null if there are not that many Parts in your string so not an issue to have extra functions).
var text combinedlist = ToText([Combined Text Summary Field]);
Split(
List("; ",
Part($combinedtext,1,";"),
Part($combinedtext,2,";"),
Part($combinedtext,3,";"),
Part($combinedtext,4,";"),
Part($combinedtext,5,";")
)
)
Since I wanted this field to be editable, I then used an automation to copy the result from the Formula field into a regular Multi-Select Text field, and now I can modify the values if I'd like.
Note that I needed the ToText() and List() functions only because I was summarizing existing summary fields (combined text of combined text) and therefore needed to split my field beyond just the first layer into the full semi-colon-separated list. If I was going straight from a simple text field that is already in list (semi-colon separated) format to the Multi-Select Text, I believe you can just use the Split() function.
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Oana Toma
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