I have managed to reproduce this issue on a different project once on Windows in Chrome by accident. However, I was not able to do it again later on any project. Unfortunately, no one could reproduce this again or provide more details.
We have also checked browser extensions, but there were no “aggressive” extensions which could do this effect.
Here is the second content type, where this issue happened for me:
<?xml version="1.0" encoding="UTF-8"?>
<content-type>
<display-name>Product</display-name>
<super-type>base:structured</super-type>
<form>
<input name="composition" type="TextLine">
<label>Composition</label>
<occurrences minimum="0" maximum="1"/>
</input>
<input name="price" type="Long">
<label>Current price</label>
<occurrences minimum="1" maximum="1"/>
</input>
<input name="finalPrice" type="Long">
<label>Final price</label>
<occurrences minimum="0" maximum="1"/>
</input>
<input name="mainImage" type="ImageSelector">
<label>Main image</label>
<occurrences minimum="1" maximum="1"/>
<config>
<allowPath>./*</allowPath>
</config>
</input>
<input name="swatch" type="ImageSelector">
<label>Swatch image</label>
<occurrences minimum="1" maximum="1"/>
<config>
<allowPath>./*</allowPath>
</config>
</input>
<input name="variations" type="ContentSelector">
<label>Variations</label>
<occurrences minimum="0" maximum="0"/>
<config>
<allowContentType>product</allowContentType>
</config>
</input>
<input name="images" type="ImageSelector">
<label>Images</label>
<occurrences minimum="0" maximum="3"/>
<config>
<allowPath>./*</allowPath>
</config>
</input>
<input name="description" type="HtmlArea">
<label>Description</label>
<config>
<exclude>*</exclude>
<include>alignleft alignright | bold italic | bullist numlist | link unlink</include>
</config>
</input>
<input name="inventory" type="Long">
<label>Inventory</label>
<occurrences minimum="0" maximum="1"/>
</input>
<item-set name="sizes">
<label>Available sizes</label>
<items>
<input name="title" type="TextLine">
<label>Size</label>
<occurrences minimum="1" maximum="1"/>
</input>
<input name="amount" type="Long">
<label>Amount</label>
<occurrences minimum="0" maximum="1"/>
</input>
</items>
<occurrences minimum="0" maximum="0"/>
</item-set>
<input name="weight" type="Double">
<label>Weight</label>
<occurrences minimum="1" maximum="1"/>
</input>
<input name="digital" type="CheckBox">
<label>Digital</label>
<occurrences minimum="0" maximum="1"/>
</input>
<input name="preorder" type="CheckBox">
<label>Preorder</label>
<occurrences minimum="0" maximum="1"/>
</input>
<input name="discontinued" type="CheckBox">
<label>Discontinued</label>
<occurrences minimum="0" maximum="1"/>
</input>
<input name="type" type="ComboBox">
<label>Item type</label>
<occurrences minimum="1" maximum="1"/>
<config>
<option value="ticket">Ticket</option>
<option value="clothes">Clothes</option>
</config>
</input>
<input name="ticketType" type="ComboBox">
<label>Ticket type</label>
<occurrences minimum="0" maximum="1"/>
<config>
<option value="regularTicket">Regular</option>
<option value="legendaryTicket">Legendary</option>
</config>
</input>
<input name="generateIds" type="Long">
<label>Ids amount</label>
</input>
</form>
</content-type>
