Спасибо! Помогло

sudo chmod -R 777 .joxi

Полный лог: http://pastebin.com/QxVsDRiD

Основная часть, которая может быть интересна:

1. --------------------------------------------------
2. QDeclarativeExpression: Expression "(function $x() { return (surface.width - selector.rubberRectRight < 115) ? selector.rubberRectLeft - width - 10 : selector.rubberRectRight + 10 })" depends on non-NOTIFYable properties:
3. SurfaceWidget::width
4. implicitWidth 130 210
5. qrc:/qml/qml/Components/ToolTip.qml:104: TypeError: Result of expression 'toolTip.update' [undefined] is not a function.
6. onTriggered 37 25
7. onVisibleChanged * 1
8. onVisibleChanged * 2
9. onVisibleChanged * 3
10. toolx = 1064 tooly = 637
11. onVisibleChanged * 1
12. QIODevice::write (QFile, "/home/vyacheslav/.joxi/tmp/1471883757796.jpg"): device not open
13. QIODevice::read (QFile, ":/certificate/joxi.pem"): device not open
14. QIODevice::write (QFile, "/home/vyacheslav/.joxi//proxy_connect.log"): device not open
15. qrc:/qml/qml/Components/Window.qml:113:9: QML Item: Cannot anchor to an item that isn't a parent or sibling.
16. qrc:/qml/qml/Components/Window.qml:113:9: QML Item: Cannot anchor to an item that isn't a parent or sibling.
17. QIODevice::read (QFile, ":/certificate/joxi.pem"): device not open
19. onVisibleChanged * 1
20. implicitWidth -1 170
21. implicitWidth 0 170
22. implicitWidth 0 170
23. qrc:/qml/qml/Components/Window.qml:113:9: QML Item: Cannot anchor to an item that isn't a parent or sibling.

Да, проблема постоянная.

ОС: Ubuntu 16.04.1 LTS

Последняя попытка: http://joxi.ru/8AnW5ZDIVR3lrO

Никаких специфических настроек фаервола нет.