Your ROOT_URL in app.ini is http://git.osmesh.ru/ but you are visiting http://91.221.70.94:3000/MOS/OpenBoard/blame/commit/2aee390105b4d2e23f52df7bbd88247ce35109b6/README.md
You should set ROOT_URL correctly, otherwise the web may not work correctly.
OpenBoard is an open source cross-platform interactive white board application designed primarily for use in schools. It was originally forked from Open-Sankoré, which was itself based on Uniboard.
Supported platforms are Windows (10+), OS X (10.13+) and Linux (Ubuntu 20.04 is the only officially maintained platform, but many others are reported by the community to work).
The latest version (1.6.1) can be compiled with the latest open source binaries of Qt 5.15. While it has been shown to work with Qt 5.9 or any other version in between, we recommend that you use the latest version you can.