qmltocpp.exe is running very slow

Qt for MCU user informed following:
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We have been so far using Qt for MCUs 2.2 and are now in the process of migrating to Qt for MCUs 2.7. We are now converting our old CMakeFiles.txt files to QmlProject files according to the QmlProject manual and the migration guide.

We are still in quite early stage of migration, but I have so far noticed that the qmltocpp.exe runs seem to be very slow as compared to our earlier dev environment in older SDK. We have about 200 QML files in our project and it looks like each QML file is processed one-by-one and processing one file takes about 5 seconds. So the whole build takes more than 15 minutes... In earlier SDK this step has run very quickly, roughly in 1 minute.

Are there some known slow-downs related the qmltocpp.exe tool? Can it be configured to run several instances in parallel, since now it looks like the QML files are processed sequentially instead of in parallel? My computer's CPU load is still small, since it looks like only one core at a time is running qmltocpp.exe.
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