Support » Plugin: Image Comparison » Update 1.2.0 damages all existing image comparisons

  • We noticed that all image comparisons were replaced by the 2 images below each other, so there was no comparison functionality anymore. After disabling all other plugins and switching to a default theme, the issue remained the same. So I had to do a rollback to version 1.0.1 and everything worked again. Can you please check and fix this?

    How to reproduce:

    1. Install Image Comparison 1.0.1
    2. Create a page or post with an Image Comparison block
    3. View the post to verify it’s working
    4. Update Image Comparison to 1.2.0
    5. Refresh the page and see the issue
Viewing 6 replies - 1 through 6 (of 6 total)
  • Plugin Support Faria Aarin


    Hello @josklever,

    I’m sorry to hear that and thank you for your instructions. Please allow us some time. I’ll try to reproduce the issue and will get back to you soon.

    Thank you for your patience.

    Plugin Support rafinkhan


    Hi @josklever,

    I hope you are doing well. First of all, we are sorry about the inconvenience caused. Anyways, in our recent update, we have made massive changes to comply with the recommended Gutenberg structure and added lots of new controls in the Image Comparison block which you can see in the changelog.

    Previously, we used to register our block here:


    But, we had to change the “Naming Conventions” to comply with the Gutenberg guidance (which wasn’t introduced when we created our blocks) and have registered our block here instead:


    As a result, you are facing the issue with the new update and you will have to create the Image Comparison block freshly. I hope you understand.

    Anyways, just to point out, we have been constantly trying to improve our Image Comparison block. We have introduced the following new features with the last update:

    Added: Responsive controls
    Added: Margin, padding option in wrapper
    Added: Content alignment, label alignment
    Added: Design customizable option for label
    Added: Advance and responsive typography option
    Added: Responsive preview edit option

    Thank you!

    • This reply was modified 2 months, 3 weeks ago by rafinkhan.
    Thread Starter Jos Klever


    Hi @rafinkhan,

    I understand that you have changed how the plugin works, but in that case you should convert the existing content to the new format, so it will keep working.

    In this case we are talking about a non-commercial website that’s managed by a couple seniors (spending a lot of their free time as volunteers) with a lot of articles about the history of their neighborhood. That’s why they are using the image comparison plugin. It would be a lot of work to recreate that content. We first need to find all the articles using this block in a collection of thousands of articles and then they have to be recreated.

    So I don’t understand that you make that our problem and that of all the other existing users and I hope you can create a migration function (or script or plugin or whatever) to fix this in the next update.

    Plugin Support rafinkhan


    Hi @josklever,

    Actually, migration wouldn’t be possible since we have changed the naming conventions. So, there’s no way to get back your previously designed blocks.

    It could be really frustrating which we can understand but we had no other choice by the way. Cause, we eventually had to update it to comply with the Gutenberg guidance at some point.

    I hope you understand. Thank you!

    Thread Starter Jos Klever


    So you just turn your back on all your existing users? 😮

    You’re making it sound like a very clear change and users working with version 1.0.1 (before updating or after a rollback) have a working site. It should be possible to convert existing blocks to the new format, because you can still access them. In the end it should just be a search/replace on the posts table or something. That’s why I don’t understand you say you can’t get back previously designed blocks.

    If this can’t be implemented via the plugin, I would appreciate it if you can give directions on what to change via the database or something. Although in that case you would still desert the users that don’t have the skills to edit the database directly.

    PS: Please don’t mark a topic as resolved, when it’s not resolved!

    Moderator Marius L. J.



    I’d like to share some helpful resources here, as it would actually be possible to resolve this in a programmable manner, but the concepts are not always super obvious, in part due to the names of the features.

    Your first course of action should definitely be the renaming of the block and its namespace, after changing a namespace, you could provide an upgrade path which would replace the post content on a site from the old to the new block name, this could be achieved with either looping over posts using WP_Posts, or the more performant approach of using WPDB.

    Once that is done, we could address the changed markup, this is the slightly ocnfusing part, but the block editor supports Deprecations (which normally means removed features, but not in this situation, here it means “changes to your block markup”).

    You can read more about it at, but in short it lets yo udefine the old, and new, markup, so that blocks will automatically migrate to the newer iteration (and yes, you can add multiple deprecations if you make multiple changes to the markup over time). This should hopefully help with the second scenario and help get you situated in the long run.

Viewing 6 replies - 1 through 6 (of 6 total)
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