Your LimeSurvey version: 3.25.19
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We have created our own theme which is an extension of vanilla. Everything in accordance with the documentation. We need to update the views in this theme. For example, some configuration option (XML) has been added, or the colors have changed, and sometimes we even change something at the level of views by plugins.

1. Resetting the theme is not an option as it removes the old theme and creates a new one, which in effect restores the global settings to their default values, and deletes all individual settings in the surveys.
2. force_xmlsettings_for_survey_rendering = true - it is absurd in production and generates errors wherever plug-in views are implemented.
3. assetsversionnumber decrementation - reloads views but not theme configurations. Although decreasing the resource version number is a strange approach for us (incrementing will prevent refreshing the view after comfortUpdate).

Any other suggestions for reloading views (assets) and configuring the theme without resetting?

In my opinion, changing the version of the theme or the last_update value should translate into its update. Unfortunately, in the case of extended vanilla in the database, it sets api_version and the version from the parent theme, although the latter still sets to NULL and last_update also NULL.

Please note that in the next version of LimeSurvey (5), the tags have been changed:

api_version is now apiVersion
last_update is now lastUpdate

I am not sure if this is also the case for LimeSurvey 3.

When i update SkelVanilla i TRY to make it compatible for new settings, for example option.value == 'off' or option.value is empty .

About default update (color) : you must edit the option of the 1st parent theme. You can not update via xml.

Else about «Resetting the theme» by core, i really thinks this feature is broken. Nobody can really use it.
It must allow a solution for "Update only" child theme, and reset only the option of the 1st parent (to current xml).

I am just after testing in the production environment, he does not see my changes at all.

Revision change in assetversionnumber, nothing has changed, I can still see views formatted the old way. For me, this is a kind of abstraction so that you normally cannot get the browser to load new assets.

What change ?
XML ?
CSS ?
HTML ?

CSS: assetversionnumber can do the trick (or reset whole assets)
HTML : in general it work, but you can clear all tmp/runtime/twig_cache to be sure
XMS : no real way, except edit m,aullay each "non inherit" survey or reste whole.

Thanks to Denis, I already know how to proceed. Although I believe that such solutions should be provided by the application, such as reloading the theme configuration itself.

It's a drama with XML because you need to know exactly what has changed and apply those changes to your theme configuration in the advanced options. The quickest way to achieve this is to reset the themes, but in production, it's the worst-case scenario. It's better to do this earlier in the development environment and just roll over the changes.

In my opinion, there should be a mechanism, i.e. asset reset in the general configuration, which also refreshes the theme (xml) and updates css and html files, i.e. twig_cache.

About CSS : just save any file in theme editor already reset the asset for THIS theme only

Elee about XML , i know …
bugs.limesurvey.org/view.php?id=14605
bugs.limesurvey.org/view.php?id=8426