TypeKeys doesn't work for GTK controls. Alphanumeric chars are not typed.

Description

What steps will reproduce the problem?
1. Use some GTK controls. I used Open file dialog in MonoDevelop
2. Assume cursor is in the path editbox. Editbox text contain "zxxy". Cursor is 
between z and x.
3. do mydlg.TypeKeys("{RIGHT}a+bc{RIGHT}")

What is the expected output? What do you see instead?
Editbox text now contain "zxBxy", cursor is between x and y. Chars a and c were 
not typed in.

What version of the product are you using? On what operating system?
Python 2.7 win/x86
Win7 Home Premium x64

Please provide any additional information below.

Contributor guide

Tech stack

python

Domain

testing

Issue type

bug

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-2 days

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

mostly clear

Prerequisites

Knowledge of pywinauto's keyboard input handlingUnderstanding of GTK window controls

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

30

Research direction

Investigate the TypeKeys method in pywinauto's keyboard handling code, likely in pywinauto/controls/keyboard.py. Look for any special handling for GTK controls or fallback mechanisms. Check if the issue is related to modifier keys (e.g., Shift) being sent incorrectly. Examine the Microsoft UI Automation (UIA) or Win32 API calls used for typing text. Consider reproducing with a simple GTK application to isolate the problem.