DSH web shell mobile adapter plugin

Key features

• Overlay sidebar drawer — opening the sidebar on a phone floats it over the content with a scrim instead of squeezing the main column to 110px
• A mobile adapter for the DeepSeek Harness (DSH) web shell.
• New-session screen on a phone (hero + composer with a workspace selected, laid out for the narrow viewport)
• Overlay details panel — the tool-details panel opens as a right-side overlay and never squeezes the conversation.
• Non-overlapping composer — the mode buttons and the model selector wrap onto separate rows instead of covering each other.