Ubuntu – Increasing the number of recently used items in KDE

I have recently switched to Kubuntu 17.04 and one of the things I miss most about my previous GNOME-based setup is the ability to search through a long chronology of my recently used files.

From what I understand, GNOME uses the Zeitgeist framework to keep track of recently used files which can record user activities across weeks, months, or even years.

KDE, on the other hand, seems to only be able to track 10 recently used items at a time which are stored as .desktop files under ~/.local/share/RecentDocuments/. There's also .local/share/recently-used.xbel, which is under no such restrictions. But that file only seems to be used by a select few apps, most of them not part of KDE itself.

So I guess my main question is: How do I increase the number of recently used items that KDE keeps track of? – be it by changing that limit of 10 RecentDocuments, forcing KDE to use recently-used.xbel, or any other method you can think of.

Some options I have tried so far:

• installing Zeitgeist under KDE and linking it up to a Zeitgeist-enabled quick-launcher like Synapse – does not seem to work with KDE apps
• using Baloo as a replacement for activity-based file tracking – while you can use Baloo to index most of your file system, it's not the same as having the most relevant results drawn from your recently used files. Baloo also seems to have trouble indexing some files, e.g. hidden config files (even with the respective option to track hidden files enabled)