I'd suggest as a minimum upgrading to MX 18.211.5.2 being the current Stable which we've been running on all our MX's including MX250 for past 5 weeks. OR take a punt and use the Stable release candidate MX 19.17.7.2 as in the screenshot where I've u...

IMPORTANTEven if disabling Intrusion detection and prevention is the fix surely your risking your network's security hence I'm not disabling the feature.

Spokes with MX250 and MX450 constant reboots.Hub with MX450 lost connectivity but didn't reboot.All our MX67s and MX85s been fine luckily.