To follow-up on this. We've been running v1.49.0 and v.1.50.0 side by side for a few days with the same settings and actions performed on each and haven't detected any memory leaks or any significant difference in memory usage between the two versions.
In both cases, the memory footprint increases during the day as price data for the charts is collected, but that is freed up as expected when the markets are removed from Guardian. With all markets removed, and the log page cleared, the footprint is currently sitting at 110MB for each version.
We used stored values in 1.50.0 to attempt to replicate what you saw and signals in v1.49.0 to be as similar as possible.
We'll close the issue for now, but if you (or any other forum member) run side by side comparisons and spot an area of concern, we'll take another look. In that situation, a description of all actions (and duration) applied to the versions would be very useful in attempting to recreate.