Bug：Abnormal initialization width transition in certain situations #242
Description
Hello,
I used your splitpane library in the project and found that in some cases, there may be a transition effect from an initial width of about 50% to size. The impact is that when opening a page without any operation, there is a visible width transition effect, which causes the width of a certain pane to change and the layout of the page elements to change significantly.
The following is a reproduced GIF image
I provided an online address that can be fully reproduced，The code source repository is here.
When there is an input tag with type password and default content on the page (the same issue occurs with element plus's el input), the reproducible problem mentioned above will occur.
After analysis, it is highly likely that the issue is due to initialization causing the width/height attribute in the style to not be assigned the correct value in a timely manner, resulting in a transition effect where there is no value initially, but a valid value is obtained later on.