Steps to repro:

1. Open Unity 5.4.0b25;
2. Create new project or open existing one;
3. Choose Help -> About Unity;
4. Observe the Console.

Actual result:

'String too long for TextMeshGenerator. Cutting off characters.
UnityEditor.HostView:OnGUI()'

error is displayed in the console (see attached actual.png screenshot).
Regression introduced in 5.4.0b25.

Possible reason for this bug is that string with Unity employees is currently overflowing allowed string size within this current popup window.

Expected result:
The error should not be displayed after opening 'About Unity' page.

Notes:
- Reproducible in 5.4.0b25;
- Not reproducible in 5.4.0b24, 5.3.5p1;
- Reproducible on both Windows 10 and OSX 10.11.5;
- The bug may also reproduce when opening existing project or saving scene/project - in this case error is triggered randomly.