Crash report Normal Mode => https://crash-stats.mozilla.com/report/index/a28b703f-3b23-4c52-b030-907d22160203 Crash report Safe Mode => https://crash-stats.mozilla.com/report/index/057bb325-f0d9-407b-bc04-878442160203

Looks like we're crashing in layout code. XML code could easily be the cause but wdyt, Jet?

OOM crash on a big ( 28MB ) XML file. I couldn't repro the crash but can see how it can happen on low-memory machines. It looks like we're OOM crashing in arena-allocated memory so we're protected there (Mats: please confirm my assumption.) The Firefox feature that shows the collapsible tree structure (unlike Chromium's plain text dump) uses up significantly more memory. Perhaps we should consider not displaying the tree structure for XML > big_size?

Yeah, those crashes are safe OOM aborts. I think this is basically a dupe of bug 231925 / bug 197956. Displaying XML as plaintext sounds fine to me, with or without a threshold. I'd rather do it unconditionally since it simpler, and we can then remove the "pretty print" code since it appears unmaintained.