Managing UWP WebView overall memory consumption over extended periods of time

Question

TL;DR

We are looking for a method to force a UWP Webview to clear any cached assets/memory for our library. Our goal is to be able to re-use the same WebView without calling methods that may adversely impact other WebViews in the same host application.

Overview:

We maintain a C# SDK which utilizes a WebView to display advertisements. Our high level workflow for an ad on a single page display involves:

1. Creating a WebView when a user wishes to display an ad. We are running the UWP webview as a SeperateProcess.
2. Using the WebView's "NavigateToString("")" method to load some arbitrary HTML/JavaScript into the webview
3. Re-using the same WebView to display another advertisement using "NavigateToString" after a 20-30 second interval.
4. Setting the WebView back to about:blank / empty string after the advertisement has been removed from the XAML tree.

The problem:

We are observing that the WebView process' memory usage continues to increase underneath the hood. Our expectation is that after we navigate the webview to a different HTML/JS fragment, we should observe a drop after a noticeable period of time. We are using ProcessExplorer to observe the peak working set and threadcount of the WWAHost.exe process. We confirmed that we do not have any leaks in managed memory.

What we've tried:

UWP App WebView Leaks Memory, doesn't clear images - We are currently using this. It appears to slow down the gradual increase over an observation period of 12 hours. After we load a new advertisement, we wait about a minute and we notice a decrease in the working set memory. But this approach is a bit "hacky".

How to clear UWP WebView cache? We've tried to do this, but we did not observe any noticeable results. In addition, we had concerns about using this method given it appears to apply this to ALL WebViews (some of which we may not even control) What does this do underneath the hood?

Additionally, we're aware that we could in theory force a GC.Collect() - but we'd rather not do this if we can help it.

Question

Is there a graceful way to force the WebView's cache to clear? The current method we are employing appears to work somewhat, but we'd like to know if there are any other options on the table that we haven't yet found.

We'd appreciate any help / insight from the community! Happy to provide more information as necessary.