Bug ID 436201: JavaScript can misbehave in case of the 'X-UA-Compatible' META tag when a client uses IE11

Last Modified: Aug 19, 2026

Affected Product(s):
BIG-IP APM(all modules)

Known Affected Versions:
11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 11.6.1, 11.6.1 hf1, 11.6.1 hf2, 11.6.2, 11.6.2 hf1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3

Fixed In:
12.0.0, 11.5.3

Opened: Oct 31, 2013

Severity: 3-Major

Related Article: K16109

Symptoms

JavaScript can misbehave when encountering the 'X-UA-Compatible' META tag from clients using Microsoft Internet Explorer 11.

Impact

Web application malfunction.

Conditions

Internet Explorer 11 and meta http-equiv='X-UA-Compatible' content='IE=10'.

Workaround

Use an iRule.

Fix Information

JavaScript now correctly handles the X-UA-Compatible meta tag from clients using Microsoft Internet Explorer 11.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips