Hi, Thanks for all your input till now.
I now managed it to get it build on i386 successfully on buildds (5.7.1+dfsg-2)  so it uses less RAM but still it needs around 15GB disk space to build. It actually also used to much RAM for an successfull amd64 build on buildds. The fix I did was to disable all debug symbols for all archs (including amd64), because all buildds do not have more than 4GB of RAM :( So QtWebEngine can't be rebuild at porterboxes with this limit and debug symbols activated. Can this be improved somehow, so I still can push source only uploads? mipsel and armhf builds still look like they are not happy with the amount of build space. It looks like their buildd disk space limit is 8GB. Are there buildds with bigger disks? Never the less QtWebEngine is a NEW package and only amd64 is RC for now, so you may have more important tasks to do... Best Regards, sandro  https://buildd.debian.org/status/logs.php?pkg=qtwebengine-opensource-src&arch=i386
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