We have a request to freeze both the header and first column of Pega's legacy hierarchical table. Pega doesn't support this at the moment, but it would be useful from a usability standpoint when tables have many rows and many columns that require excessive scrolling. It would help the users keep track of the context of the information they are looking at regardless of how far they scroll. I believe this request is possible with Pega 8's new optimized hierarchy table. However, there were limitations with Pega 8's optimized hierarchical table in terms of functionality (filtering rows and loading expanded rows automatically), which is why we had to stick with the legacy hierarchical table.
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