When you render a video, there is an option to "render using proxy clips". The last used value of this is remembered when you close the render dialog and open it again later. Though, this setting is not remembered when you restart Kdenlive 15.04.0. Reproducible: Always
In current git versions of Kdenlive, the proxy clip settings are in the Project/Project Settings menu. If you change these settings, save your project and quit Kdenlive, then start Kdenlive, these settings will not be restored. If you load your project however, the proxy settings will be restored. Strangely, the thumbnail settings above the proxy settings gets stored independent of the project file. So there is at least a minor inconsistency issue. I'm not sure what to suggest. One could try moving some of these settings elsewhere, one could change either proxy settings to be global or thumbnail settings to be local or something else. Here's a video demonstrating the settings and how they (don't) get saved: https://youtu.be/ZztUq0iPcFI
Tested with Kdenlive 16.04.1, only some settings get saved (and you have to actually render for this to happen). Encoder speed: yes 2 pass: couldn't test Scanning: yes Rescale: yes Export audio: no Stem audio export: no Overlay: yes Render using proxy clips: no Play after render: yes Export metadata: no IMHO, every setting should be remembered (including the checkbox "More options" itself).
Moved to phabricator: https://phabricator.kde.org/T9879
Reopening as Phabricator is deprecated.
Please tet with Kdenlive_Nightly_Appimage https://binary-factory.kde.org/job/Kdenlive_Nightly_Appimage_Build/lastSuccessfulBuild/artifact/ Render Dialog: remember state of "more options" was implemted https://invent.kde.org/multimedia/kdenlive/-/commit/fbeee949fc8cb8809ad0c29ebb1ee06fd6bb0efd
Tested with nightly 21.03.70: Fixed Thanks!