This is an updated thread replacing the previous ones that have been archived.

MX 7 and 6 only function on Windows 7 or later.

Chrome 110 and later only function on Windows 10 and 11. Earlier versions of Windows will remain on Chrome 109. Chrome 110 and up function in the UA for all versions of Windows.

MX 7.3 series only function on Windows 10 and above at present.

From MX 7.1.8.7000 (March 2024) it is possible to change the User Agent in MX 7 using the traditional internal UA modifier/selector in Settings/Advanced/ Experiments.

You can also use extensions from the chrome store. I personally use

https://chrome.google.com/webstore/detail/user-agent-switcher-and m/bhchdcejhohfmigjafbampogmaanbfkg (recommended). There are lots of others.

The Qupzilla browser is now obsolete and is no longer being developed.

From December 2022 I have in incorporated Edge and Opera as standard. These UAs break Youtube. Use standard Maxthon UA: just disable chosen UA extension in Extensions and reload tab. NOTE From version 7.1.8.9400 Live Chat seems to work correctly.

With Windows 11 the system has changed to User Agent Client Hints (UA-CH). More information to follow as Browsers adapt to this new system. Google the term for the latest relevant information as it is adopted and evolves.

You can also modify the User Agent Request Header and reduce the Minor browser version using flags. Go to mx://flags/.

Thanks to Imanerd.

Updated 13th August 2025

MX 5.3.8 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8.2100 Chrome/139.0.7258.128 Safari/537.48 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8.2100 Chrome/139.0.7258.128 Safari/537.48 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:1

Mozilla/5.0 (compatible; Windows NT 6.3; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8.2100 Chrome/139.0.7258.128 Safari/537.48 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11

Mozilla/5.0 (compatible; Windows NT 10.0; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8.2100 Chrome/139.0.7258.128 Safari/537.48 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.2.2 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2.7600 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2.7600 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8.1

Mozilla/5.0 (compatible; Windows NT 6.3; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2.7600 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11

Mozilla/5.0 (compatible; Windows NT 10.0; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2.7600 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.3.1 Series These function on other series as well.

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; U; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.3.1.8000 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

Truncated Versions. Thanks to Imanerd.

MX 5.3.8 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8.1:

Mozilla/5.0 (compatible; Windows NT 6.3; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/5.3.8 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.2.2 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8.1:

Mozilla/5.0 (compatible; Windows NT 6.3; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.2.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.3.1 Series These function on other series as well.

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ (KHTML, like Gecko) Maxthon/7.3.1 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

Minimalist Version Thanks to Imanerd.

MX 5.3 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/5.3 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/5.3 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.106

For Windows 8.1:

Mozilla/5.0 (compatible; Windows NT 6.3; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/5.3 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/5.3 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.2 Series These function on other series as well.

For Windows 7:

Mozilla/5.0 (compatible; Windows NT 6.1; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/7.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8:

Mozilla/5.0 (compatible; Windows NT 6.2; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/7.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 8.1:

Mozilla/5.0 (compatible; Windows NT 6.3; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/7.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/7.2 Chrome/139.0.7258.128 Safari/537.36 OPR/120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

MX 7.3 Series These function on other series as well.

For Windows 10 & 11:

Mozilla/5.0 (compatible; Windows NT 10.0; WOW64; IA64; en) AppleWebKit/599.0+ Maxthon/7.3 Chrome/139.0.7258.128 Safari/537.36 OPR/1120.5543.161 QupZilla/2.2.6 Edge/138.0.3351.109

Thread reposted as original is now closed to editing.