Administrator
Advocate IHi MS team,
Thanks for some of these updates (especially the donut chart centre value which has been requested for so long), however the current update has created a really messy situation for us given how much we rely on our custom JSON theme to ensure brand compliance, and the fact we now have to release a new theme file to prevent styles for new reports breaking by default (unless every user remembers to revert the base theme to 'classic' 2026, which they won't).
Specifically, the default slicer behaviour still reverts to the list rather than the dropdown. However, if it's still planned that it will eventually revert to a dropdown style as a default, that would mean swapping around our current defaults would end up being redundant anyway, and as you're aware, changing style presets after the fact (i.e. renaming/removing them after application) leads to formatting errors and in extreme cases a break of function. This is significant when it can potentially effect hundreds of embedded PBI reports available to external customers.
I've included the previous posts about this with responses from DataZoe below for context, please advise if there's a timeline for when this will be 'fixed/attempted again', thanks.
My original query above (from July update thread)Data Zoe's responseMy follow-up with further questionAlso, if you can respond to my query from last month about the image visual functionality (copied below, also from the July comments thread) that would also be helpful, but the priority is definitely the default slicer behaviour/formatting mentioned above.
Finally an update for alyssaphil, this month the PBI release updated in the app store version within 24 hours as expected, so it seems last months delay (thankfully) was an anomaly.
I'm also looking for a best practice for custom theme JSON. As im seeing it now the best thing to do is start with the modern theme as base and only add specific elements. Am I right?
My current custom theme is behaving very weird in some areas like for example font types and sizes for totals.
Advocate IIn our case we have very specific requirements due to the context of brand compliance, UI/UX consistency for commercial product etc.
However, if you're broadly 'open' to MS's (quite significant) changes to chart styles and functionality (plus slicers etc.) then yes, the ideal approach is to leave as much possible to the 'base theme' and only override the formatting you require to be bespoke, keeping your theme file as small and easy to manage as possible. This is also mentioned on the MS general (custom) theme page.
learn.microsoft.com/en-us/power-bi/create-reports/report-themes-create-custom (for some reason I can't post links so please add the usual 'https' if you want to visit it [or this may work by default, not sure])
This was the approach we took several years ago (back when navigators didn't exist and the default text box didn't even feature bullets!) when we first built our theme file, but since then we now have a detailed and well functioning UI/UX setup, so I've had to do the opposite and add multiple formatting values to better control the interface design. (Ironically though the 'new' donut chart inner radius now matches our original bespoke value of 70%.) Also, I've added multiple bespoke features using custom presets to facilitate custom icons and component-like bespoke formatting functionality etc., so for us there's no dialing it back at this point.
Anyway, the TL;DR is that yes, unless you require a specific set of formatting values and already have a well established 'custom' look and function in place, the path of least resistance is to leave as many default settings in place as you reasonably can, and only change/override the settings you need to.
Just bear in mind as MS makes changes with certain updates, you may see multiple changes to your reports depending on previous defaults being modified with certain releases, especially around areas like spacing, previous items that were switched off by default being switched on etc.
