Today I have may a little life savior for you Simmers. You want to change your theme and suddenly this annoying message pops up? Still can’t fix it? There is a simple way to do so. If you follow this instruction it should be quickly solved.
Make sure that you are in the “Edit theme” Mode. This Error message only pops up if you tried to edit your new theme and doesn’t let you save it due to the error. It’s because the code you’re using still contains old “http” tags which don’t provide the security standard as “https” and Tumblr made it now standard to use only “https”.
Click Ctrl+F: The Search/Replace Bar should pop up like this.
Type in search “http” and replace it with “https” by clicking on “All”. The pink box (below) shows how it should be replaced automatically after you said “All”.
This Code contains in such cases “http” and “https” so that’s why it doesn’t work. Therefore you replaced only “http” now we need to fix our mess which is now called ‘httpss”. You need to proceed as you just did the same way again. Enter in search “httpss” and replace it with “https” and confirm to replace “All” again ;). As you can see below.
After you’re done click on “Save” the Button for save should disappear and no messages should pop up that the code is messed up because you just fixed it. Now you can exist and when you get back you can edit changes as you wish.
Hope this problem can solve for your blogs . Source Post Here