Can't upload profile due to "Out of Memory" error

I tried to record native and Javascript allocations while running some automation with Marionette. Therefore I disabled all the other threads only only left those two, and changed the buffer size to 450MB.

Uploading the profile errored with the following failure:

[Exception... "Out of Memory" nsresult: "0x8007000e (NS_ERROR_OUT_OF_MEMORY)" location: "JS frame :: https://profiler.firefox.com/795a166e4793db308baa.bundle.js :: uc/r< :: line 95" data: no]

Here the full stack:

```
Exception { name: "NS_ERROR_OUT_OF_MEMORY", message: "", result: 2147942414, filename: "https://profiler.firefox.com/795a166e4793db308baa.bundle.js", lineNumber: 95, columnNumber: 0, data: null, stack: "uc/r<@https://profiler.firefox.com/795a166e4793db308baa.bundle.js:95:15017\nasync*uc@https://profiler.firefox.com/795a166e4793db308baa.bundle.js:95:15037\nasync*fc/<@https://profiler.firefox.com/795a166e4793db308baa.bundle.js:99:80\nasync*$b/