dead key text input broken

What locale are you using, what keyboard layout do you use in Windows?

Locale: Latvian, keyboard layout: Latvian (aposthrope)(by Tilde ltd.) Keyboard layout has one dead key "'".

Some more data: when locale is Japanese and keyboard layout is Latvian (similar to previous), it is completely impossible to input any modified characters, inkscape completely refuses to input "'"key (pressing "'" and "a" in sequece produces just "a"; presing "'"key once or multiple times, does not inputs anything)
These data are on version 0.46 win32 and system locale is Japanese, and Keyboard layout is Latvian (by Laacz (http://laacz.lv/f/misc/apos/apostrofs_punkts_vista32.zip)(can be downloaded here))

Changing locale to Latvian, exactly replicates in first description described problem (this bug appears to be independent on exact type of dead key keyboard layout).

Also, when using Japanese locale and Japanese keyboard layout, bug [https://bugs.launchpad.net/inkscape/+bug/166632] is still present (IME input box is located near corner of program window, not at the text input site)(however Japanes text input works properly)(except of this visual issue).

also, windows was windows xp sp2 english version (non localized)

Dead key (with apostrophe key as dead key) based keyboard layouts are the most popular form of inputting Latvian language texts in computers, athough these layouts are not an official standart and are not bundled with windows.

OK. Some investigation reveals the suspected - Inkscape does not rely on Windows to deliver the correct characters. Polish keyboard layout in Windows uses tilda (~) as a dead key for Polish characters and while it works as expected in Windows it does not in Inkscape since it uses GTK input method based on the LOCALE set when Inkscape starts.

Some pointers:
http://webcvs.freedesktop.org/xkeyboard-config/xkeyboard-config/symbols/lv?view=markup
http://gitweb.freedesktop.org/?p=xorg/lib/libX11.git;a=blob;f=nls/en_US.UTF-8/Compose.pre
http://blogs.gnome.org/simos/2008/01/30/improving-input-method-support-in-gtk-based-apps/

It seems we need to enable lv_LV locale in Inkscape.

Does this problem still exist in the current release version (Inkscape 0.47)?

Yeah, just tested in 0.47. All attempts yield character with ' on top, instead of correctly modified character.

Still present in Inkscape 0.48.2 (Windows Vista 64bit). I've got a custom keyboard layout with the locale de-AT. Some deadkeys work but not others, e.g. ^,j = "ĵ" ; ^,w = "ŵ" as expected, but ^,t and ^,ß [sharp S on German keyboard] do nothing while they should produce "ṱ" and "ẞ", respectively.
Some combinations produce wrong characters, e.g. ^,1 = "¹" instead of "¼" ("¹" should be the output of AltGr+´, 1) Some aren't recognised as deadkeys at all, e.g. AltGr+c and AltGr+Shift+7 should be deadkeys but produce a character right away. Undefined deadkey combinations do nothing at all, e.g. ^,q should produce "^q" but does nothing.

The issue you are describing with Inkscape not handling dead keys as expected is likely due to a limitation or a bug in the software. Inkscape is an open-source vector graphics editor, and it may not always have perfect compatibility with all keyboard layouts and input methods.

To address this problem, you can consider the following steps:

Check for Updates: Make sure you have the latest version of Inkscape installed. The software developers may have fixed this issue in a newer release.

User Forums and Bug Reports: Check Inkscape's user forums, community, or bug tracking system to see if others have reported the same issue. If it's a known problem, there might be workarounds or discussions on when it could be fixed.

Configure Keyboard Layout: Ensure your operating system's keyboard layout settings are configured correctly. Sometimes, issues with dead keys may be related to the operating system settings rather than Inkscape itself.

Temporary Workaround: If Inkscape doesn't handle your keyboard layout correctly, you might need to use a temporary workaround. For example, you can use an external text editor to input text with dead keys and then copy and paste it into Inkscape.

Contribute to the Open Source Community: If you have the technical knowledge and time, consider contributing to the open-source community by submitting a bug report or even a code fix. This can help improve the software for everyone.

Try Different Software: If the issue persists and you rely heavily on dead keys, you might consider using an alternative vector graphics editor that doesn't have this problem.

Keep in mind that software issues can vary depending on the specific operating system, keyboard layout, and language settings. As a result, it's crucial to find a solution that works for your unique setup. Solution by https://fescoonlinebillcheck.pk/