If you update to Joomla 3.8.10, please make sure that you either do a full GitHub update of Fabrik, or disable caching for your lists (in the Advanced settings) or turn off Joomla's System Cache setting. A change in Joomla's cache code in 3.8.10 required a fix in Fabrik, which will be rolled in to the next release, but is currently only available in GitHub.
Contribute to Fabrik
Fabrik is an Open Source project - which means that to make reasonable progress with development of both code and supporting documentation, it relies on the contributions of users to supplement the time of the main development team.
If you are benefitting from the free use of Fabrik for your own projects, please consider contributing to the project by fixing bugs, writing enhancements, editing / creating wiki pages, by translating fabrik strings from english to other languages or by helping other, less experienced users by answering forum posts.
Because the Joomla world changes month-on-month, and fabrik needs to move with it, the amount of work needed to keep fabrik working is significant, and its long-term success is very much dependent on the user community contributing to recognise the benefits they gain from the software. The fabrik developers will very much appreciate any contributions you make.